With the spread of Hackers and Hacking incidents, the time has come, when not only system administrators of servers of big companies, but also people who connect to the Internet by dialing up into their ISP, have to worry about securing their system. It really does not make much difference whether you have a static IP or a dynamic one, if your system is connected to the Internet, then there is every chance of it being attacked.
This manual is aimed at discussing methods of system security analysis and will shed light on as to how to secure your standalone (also a system connected to a LAN) system.
Open Ports: A Threat to Security?
In the Netstat Tutorial we had discussed how the netstat -a command showed the list of open ports on your system. Well, anyhow, before I move on, I would like to quickly recap the important part. So here goes, straight from the netstat tutorial:
Now, the ??a? option is used to display all open connections on the local machine. It also returns the remote system to which we are connected to, the port numbers of the remote system we are connected to (and the local machine) and also the type and state of connection we have with the remote system.
For Example,
C:\windows>netstat -a
Active Connections
Proto Local Address Foreign Address State
TCP ankit:1031 dwarf.box.sk:ftp ESTABLISHED
TCP ankit:1036 dwarf.box.sk:ftp-data TIME_WAIT
TCP ankit:1043 banners.egroups.com:80 FIN_WAIT_2
TCP ankit:1045 mail2.mtnl.net.in:pop3 TIME_WAIT
TCP ankit:1052 zztop.boxnetwork.net:80 ESTABLISHED
TCP ankit:1053 mail2.mtnl.net.in:pop3 TIME_WAIT
UDP ankit:1025 *:*
UDP ankit:nbdatagram *:*
Now, let us take a single line from the above output and see what it stands for:
Proto Local Address Foreign Address State
TCP ankit:1031 dwarf.box.sk:ftp ESTABLISHED
Now, the above can be arranged as below:
Protocol: TCP (This can be Transmission Control Protocol or TCP, User Datagram Protocol or UDP or sometimes even, IP or Internet Protocol.)
Local System Name: ankit (This is the name of the local system that you set during the Windows setup.)
Local Port opened and being used by this connection: 1031
Remote System: dwarf.box.sk (This is the non-numerical form of the system to which we are connected.)
Remote Port: ftp (This is the port number of the remote system dwarf.box.sk to which we are connected.)
State of Connection: ESTABLISHED
?Netstat? with the ??a? argument is normally used, to get a list of open ports on your own system i.e. on the local system. This can be particularly useful to check and see whether your system has a Trojan installed or not. Yes, most good Antiviral software are able to detect the presence of Trojans, but, we are hackers, and need to software to tell us, whether we are infected or not. Besides, it is more fun to do something manually than to simply click on the ?Scan? button and let some software do it.
The following is a list of Trojans and the port numbers which they use, if you Netstat yourself and find any of the following open, then you can be pretty sure, that you are infected.
Port 12345(TCP) Netbus
Port 31337(UDP) Back Orifice
For complete list, refer to the Tutorial on Trojans at: hackingtruths.box.sk/trojans.txt
----
Now, the above tutorial resulted in a number of people raising questions like: If the 'netstat -a' command shows open ports on my system, does this mean that anyone can connect to them? Or, How can I close these open ports? How do I know if an open port is a threat to my system's security of not? Well, the answer to all these question would be clear, once you read the below paragraph:
Now, the thing to understand here is that, Port numbers are divided into three ranges:
The Well Known Ports are those from 0 through 1023. This range or ports is bound to the services running on them. By this what I mean is that each port usually has a specific service running on it. You see there is an internationally accepted Port Numbers to Services rule, (refer RFC 1700 Here) which specifies as to on what port number a particular service runs. For Example, By Default or normally FTP runs on Port 21. So if you find that Port 21 is open on a particular system, then it usually means that that particular system uses the FTP Protocol to transfer files. However, please note that some smart system administrators delibrately i.e. to fool lamers run fake services on popular ports. For Example, a system might be running a fake FTP daemon on Port 21. Although you get the same interface like the FTP daemon banner, response numbers etc, however, it actually might be a software logging your prescence and sometimes even tracing you!!!
The Registered Ports are those from 1024 through 49151. This range of port numbers is not bound to any specific service. Actually, Networking utlites like your Browser, Email Client, FTP software opens a random port within this range and starts a communication with the remote server. A port number within this range is the reason why you are able to surf the net or check your email etc.
If you find that when you give the netstat -a command, then a number of ports within this range are open, then you should probably not worry. These ports are simply opened so that you can get your software applications to do what you want them to do. These ports are opened temporarily by various applications to perform tasks. They act as a buffer transfering packets (data) received to the application and vis-a-versa. Once you close the application, then you find that these ports are closed automatically. For Example, when you type www.hotmail.com in your browser, then your browser randomly chooses a Registered Port and uses it as a buffer to communicate with the various remote servers involved.
The Dynamic and/or Private Ports are those from 49152 through 65535. This range is rarely used, and is mostly used by trojans, however some application do tend to use such high range port numbers. For Example,Sun starts their RPC ports at 32768.
So this basically brings us to what to do if you find that Netstat gives you a couple of open ports on your system:
1. Check the Trojan Port List and check if the open port matches with any of the popular ones. If it does then get a trojan Removal and remove the trojan.
2. If it doesn't or if the Trojan Remover says: No trojan found, then see if the open port lies in the registered Ports range. If yes, then you have nothing to worry, so forget about it.
***********************
HACKING TRUTH: A common technique employed by a number of system administrators, is remapping ports. For example, normally the default port for HTTP is 80. However, the system administrator could also remap it to Port 8080. Now, if that is the case, then the homepage hosted at that server would be at:
http://domain.com:8080 instead of
http://domain.com:80
The idea behind Port Remapping is that instead of running a service on a well known port, where it can easily be exploited, it would be better to run it on a not so well known port, as the hacker, would find it more difficult to find that service. He would have to port scan high range of numbers to discover port remapping.
The ports used for remapping are usually pretty easy to remember. They are choosen keeping in mind the default port number at which the service being remapped should be running. For Example, POP by default runs on Port 110. However, if you were to remap it, you would choose any of the following: 1010, 11000, 1111 etc etc
Some sysadmins also like to choose Port numbers in the following manner: 1234,2345,3456,4567 and so on... Yet another reason as to why Port Remapping is done, is that on a Unix System to be able to listen to a port under 1024, you must have root previledges.
************************
Firewalls
Use of Firewalls is no longer confined to servers or websites or commerical companies. Even if you simply dial up into your ISP or use PPP (Point to Point Protocol) to surf the net, you simply cannot do without a firewall. So what exactly is a firewall?
Well, in non-geek language, a firewall is basically a shield which protects your system from the untrusted non-reliable systems connected to the Internet. It is a software which listens to all ports on your system for any attempts to open a connection and when it detects such an attempt, then it reacts according to the predefined set of rules. So basically, a firewall is something that protects the network(or systen) from the Internet. It is derived from the concept of firewalls used in vehicles which is a barrier made of fire resistant material protecting the vehicle in case of fire.
Now, for a better 'according to the bible' defination of a firewall: A firewall is best described as a software or hardware or both Hardware and Software packet filter that allows only selected packets to pass through from the Internet to your private internal network. A firewall is a system or a group of systems which guard a trusted network( The Internal Private Network from the untrusted network (The Internet.)
NOTE: This was a very brief desciption of what a firewall is, I would not be going into the details of their working in this manual.
Anyway,the term 'Firewalls', (which were generally used by companies for commerical purposes) has evolved into a new term called 'Personal Firewalls'. Now this term is basically used to refer to firewalls installed on a standalone system which may or may not be networked i.e. It usually connects to an ISP. Or in other words a personal firewall is a firewall used for personal use.
Now that you have a basic desciption as to what a firewall is, let us move on to why exactly you need to install a Firewall? Or, how can not installing a firewall pose a threat to the security of your system?
You see, when you are connected to the Internet, then you have millions of other untrusted systems connected to it as well. If somehow someone found out your IP address, then they could do probably anything to your system. They could exploit any vulnerability existing in your system, damage your data, and even use your system to hack into other computers.
Finding out someone'e IP Address is not very difficult. Anybody can find out your IP, through various Chat Services, Instant Messengers (ICQ, MSN, AOL etc), through a common ISP and numerous other ways. Infact finding out the IP Address of a specific person is not always the priority of some hackers.
What I mean to say by that is that there are a number of Scripts and utilities available which scan all IP addresses between a certain range for predefined common vulnerabilities. For Example, Systems with File Sharing Enabled or a system running an OS which is vulnerable to the Ping of Death attack etc etc As soon as a vulnerable system is found, then they use the IP to carry out the attacks.
The most common scanners look for systems with RAT's or Remote Administration Tools installed. They send a packet to common Trojan ports and display whether the victim's system has that Trojan installed or not. The 'Scan Range of IP Addresses' that these programs accept are quite wide and one can easily find a vulnerable system in the matter of minutes or even seconds.
Trojan Horses like Back Orifice provide remote access to your system and can set up a password sniffer. The combination of a back door and a sniffer is a dangerous one: The back door provides future remote access, while the sniffer may reveal important information about you like your other Passwords, Bank Details, Credit Card Numbers, Social Security Number etc If your home system is connected to a local LAN and the attacker manages to install a backdoor on it, then you probably have given the attacker the same access level to your internal network, as you have. This wouls also mean that you will have created a back door into your network that bypasses any firewall that may be guarding the front door.
You may argue with me that as you are using a dial up link to your ISP via PPP, the attacker would be able to access your machine only when you are online. Well, yes that is true, however, not completely true. Yes, it does make access to your system when you reconnect, difficult, as you have a dynamic Internet Protocol Address. But, although this provides a faint hope of protection, routine scanning of the range of IP's in which your IP lies, will more often than not reveal your current Dynamic IP and the back door will provide access to your system.
*******************
HACKING TRUTH: Microsoft Says: War Dialer programs automatically scan for modems by trying every phone number within an exchange. If the modem can only be used for dial-out connections, a War Dialer won't discover it. However, PPP changes the equation, as it provides bidirectional transportmaking any connected system visible to scanners?and attackers.
*******************
So how do I protect myself from such Scans and unsolicitated attacks? Well, this is where Personal Firewalls come in. They just like their name suggests, protect you from unsolicitated connection probes, scans, attacks.
They listen to all ports for any connection requests received (from both legitimate and fake hosts) and sent (by applications like Browser, Email Client etc.) As soon as such an instance is recorded, it pops up a warning asking you what to do or whether to allow the connection to initiate or not. This warning message also contains the IP which is trying to initiate the connection and also the Port Number to which it is trying to connect i.e. the Port to which the packet was sent. It also protects your system from Port Scans, DOS Attacks, Vulnerability attacks etc. So basically it acts as a shield or a buffer which does not allow your system to communicate with the untrusted systems directly.
Most Personal Firewalls have extensive logging facilities which allows you to track down the attackers. Some popular firewalls are:
1.BlackICE Defender : An IDS for PC's. It's available at http://www.networkice.com.
2. ZoneAlarm: The easiest to setup and manage firewall. Get it for free at: www.zonelabs.com
Once you have installed a firewall on your system, you will often get a number of Warnings which might seem to be as if someone is trying to break into your system, however, they are actually bogus messages, which are caused by either your OS itself or due to the process called Allocation of Dynamic IP's. For a details description of these two, read on.
Many people complain that as soon as they dial into their ISP, their firewall says that such and such IP is probing Port X. What causes them?
Well, this is quite common. The cause is that somebody hung up just before you dialed in and your ISP assigned you the same IP address. You are now seeing the remains of communication with the previous person. This is most common when the person to which the IP was assigned earlier was using ICQ or chat programs, was connected to a Game Server or simply turned off his modem before his communication with remote servers was complete.
You might even get a message like: Such and Such IP is trying to initaite a Netbios Session on Port X. This again is extrememly common. The following is an explanation as to why it happens, which I picked up a couple of days ago: NetBIOS requests to UDP port 137 are the most common item you will see in your firewall reject logs. This comes about from a feature in Microsoft's Windows: when a program resolves an IP address into a name, it may send a NetBIOS query to IP address. This is part of the background radiation of the Internet, and is nothing to be concerned about.
What Causes them? On virtually all systems (UNIX, Macintosh, Windows), programs call the function 'gethostbyaddr()' with the desired address. This function will then do the appropriate lookup, and return the name. This function is part of the sockets API. The key thing to remember about gethostbyaddr() is that it is virtual. It doesn't specify how it resolves an address into a name. In practice, it will use all available mechanisms. If we look at UNIX, Windows, and Macintosh systems, we see the following techniques:
DNS in-addr.arpa PTR queries sent to the DNS server
NetBIOS NodeStatus queries sent to the IP address
lookups in the /etc/hosts file
AppleTalk over IP name query sent to the IP address
RPC query sent to the UNIX NIS server
NetBIOS lookup sent to the WINS server
Windows systems do the /etc/hosts, DNS, WINS, and NodeStatus techniques. In more excruciating detail, Microsoft has a generic system component called a naming service. All the protocol stacks in the system (NetBIOS, TCP/IP, Novel IPX, AppleTalk, Banyan, etc.) register the kinds of name resolutions they can perform. Some RPC products will likewise register an NIS naming service. When a program requests to resolve an address, this address gets passed onto the generic naming service. Windows will try each registered name resolution subsystem sequentially until it gets an answer.
(Side note: User's sometimes complained that accessing Windows servers is slow. This is caused by installing unneeded protocol stacks that must timeout first before the real protocol stack is queried for the server name.).
The order in which it performs these resolution steps for IP addresses can be configured under the Windows registry key
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\ServiceProvider.
Breaking Through Firewalls
Although Firewalls are meant to provide your complete protection from Port Scan probes etc there are several holes existing in popular firewalls, waiting to be exploited. In this issue, I will discuss a hole in ZoneAlarm Version 2.1.10 to 2.0.26, which allows the attacker to port scan the target system (Although normally it should stop such scans.)
If one uses port 67 as the source port of a TCP or UDP scan, ZoneAlarm will let the packet through and will not notify the user. This means, that one can TCP or UDP port scan a ZoneAlarm protected computer as if there were no firewall there IF one uses port 67 as the source port on the packets.
Exploit:
UDP Scan:
You can use NMap to port scan the host with the following command line:
nmap -g67 -P0 -p130-140 -sU 192.168.128.88
(Notice the -g67 which specifies source port).
TCP Scan:
You can use NMap to port scan the host with the following command line:
nmap -g67 -P0 -p130-140 -sS 192.168.128.88
(Notice the -g67 which specifies source port).
Hope it help.
Showing posts with label Information. Show all posts
Showing posts with label Information. Show all posts
May 18, 2008
Mar 23, 2008
Common Problem With Hard Disk
The most common problems originate
from corruption of the master boot record, FAT, or directory.
Those are soft problems which can usually be taken care of
with a combination of tools like Fdisk /mbr to refresh the
master boot record followed by a reboot and Norton disk doctor
or Spinneret.
The most common hardware problems are a bad controller, a bad
drive motor, or a bad head mechanism.
1. Can the BIOS see and identify the hard drive correctly? If
it can't, then the hard drives onboard controller is bad.
2. Does the drive spin and maintain a constant velocity? If it
does, that's good news. The motor is functioning.
3. If the drive surges and dies, the most likely cause is a
bad controller (assuming the drive is cool). A gate allowing
the current to drive the motor may not be staying open. The
drive needs a new controller.
4. Do you hear a lot of head clatter when the machine is
turned on and initialized (but before the system attempts to
access the hard drive). Head clatter would indicate that the
spindle bearings are sloppy or worn badly. Maybe even lose and
flopping around inside.
5. There is always the possibility that the controller you are
using in the machine has gone south.
from corruption of the master boot record, FAT, or directory.
Those are soft problems which can usually be taken care of
with a combination of tools like Fdisk /mbr to refresh the
master boot record followed by a reboot and Norton disk doctor
or Spinneret.
The most common hardware problems are a bad controller, a bad
drive motor, or a bad head mechanism.
1. Can the BIOS see and identify the hard drive correctly? If
it can't, then the hard drives onboard controller is bad.
2. Does the drive spin and maintain a constant velocity? If it
does, that's good news. The motor is functioning.
3. If the drive surges and dies, the most likely cause is a
bad controller (assuming the drive is cool). A gate allowing
the current to drive the motor may not be staying open. The
drive needs a new controller.
4. Do you hear a lot of head clatter when the machine is
turned on and initialized (but before the system attempts to
access the hard drive). Head clatter would indicate that the
spindle bearings are sloppy or worn badly. Maybe even lose and
flopping around inside.
5. There is always the possibility that the controller you are
using in the machine has gone south.
1. If the drive spins, try booting to the A> prompt, run Fdisk
and check to see if Fdisk can see a partition on the hard
drive. If Fdisk can see the partition, that means that it can
access the drive and that the controller electronics are
functioning correctly. If there is no head clatter, it may be
just a matter of disk corruption which commonly occurs when a
surge hits you machine and overwhelms the power supply voltage
regulator. It commonly over whelms the system electronics
allowing an EM pulse to wipe out the master boot record, file
allocations table, and primary directory. Fdisk can fix the
master boot record and Norton Disk Doctor can restore the FAT
and Directory from the secondaries.
2. The drive spins but Fdisk can't see it. Try the drive in
another system and repeat the test to confirm that Fdisk can't
read through the drives onboard controller. If it sees it in
another system, then your machines hard drive interface is
bad. You can try an upgraded or replacement controller card
like a Promise or CMD Technologies (there are others) in you
machine after disabling the integrated controller in the BIOS,
but if the integrated controller went south, it may just be
symptomatic of further failures and you'd be wise to replace
the motherboard. Trying the drive in another machine also
eliminates the variable that your machines 12 volt power
output being bad
3. If you get head clatter but a constant velocity on the
drive motor (no surging), you might try sticking the hard
drive in the freezer for about 12 hours. This is an old trick
from back in the days of the MFM/ESDI driver era. This can
cause the drive components to shrink enough to make the track
marker align with the tracks. We don't see that kind of
platter spindle wear much anymore, but back in the old days,
the balancing and bearings weren't as good. Still, under the
right circumstances, it might help. It would depend on how old
the drive is and how many hours of wear have occurred. You
have to be quick to get your info off the drive when it works.
Back then, the drives were much smaller, so there wasn't so
much to copy. So, go after the important data first.
4. The drive doesn't spin. Either the onboard controller is
bad or the motor is bad (assuming you did try the drive in
another machine). It's time to hit the net and local
independent shops to see if you can locate another drive of
the same make and model that's good. Since the drive is
probably an older drive and no longer in distribution, your
best bet is to find an identical used drive. If you know
someone with the same make and model, you might be wise to try
and persuade them to sell you their drive with an offer of
providing them with a free upgraded drive. If you can locate
an identical drive, start with the controller replacement ...
this is the simplest and least invasive. If swapping the
controller doesn't produce the desire result, you can tear
into the drive and swap the motors. While you have both drive
opened up to accomplish this, scrutinize the platters, heads
and armatures. You might even hook the drive up and power it
from a system with both drives attached. This way, you could
see anything that deviates between the actions of both drives
when they are initialized. Swapping patters is unlikely to
produce any positive result. They are a balanced system like
the tires on your car and I suspect that the balance will be
different for each drive as will other variables.
5. There's always Ontrack Corp. who will attempt to recoup
your info starting at $500 and going up from there. They don't
fix and return the drive either.
If the info is all that important to you, I would seek some
professional and experience technician in your locality who
makes his living from servicing and building computer systems
... not just selling them. If you have had much experience
salvaging information from bad hard drives, your likelihood of
success is low. In the case of soft corruption, all utilities
have their eccentricities. Often times, Norton Disk Doctor
will go too far (if you let it). It's wise to just let those
utilities small steps and then have a look at the drive and
see if you can copy it off. Norton will go so far as to rename
directories and files, and even delete them or break them up
into fragments which are useless.
and check to see if Fdisk can see a partition on the hard
drive. If Fdisk can see the partition, that means that it can
access the drive and that the controller electronics are
functioning correctly. If there is no head clatter, it may be
just a matter of disk corruption which commonly occurs when a
surge hits you machine and overwhelms the power supply voltage
regulator. It commonly over whelms the system electronics
allowing an EM pulse to wipe out the master boot record, file
allocations table, and primary directory. Fdisk can fix the
master boot record and Norton Disk Doctor can restore the FAT
and Directory from the secondaries.
2. The drive spins but Fdisk can't see it. Try the drive in
another system and repeat the test to confirm that Fdisk can't
read through the drives onboard controller. If it sees it in
another system, then your machines hard drive interface is
bad. You can try an upgraded or replacement controller card
like a Promise or CMD Technologies (there are others) in you
machine after disabling the integrated controller in the BIOS,
but if the integrated controller went south, it may just be
symptomatic of further failures and you'd be wise to replace
the motherboard. Trying the drive in another machine also
eliminates the variable that your machines 12 volt power
output being bad
3. If you get head clatter but a constant velocity on the
drive motor (no surging), you might try sticking the hard
drive in the freezer for about 12 hours. This is an old trick
from back in the days of the MFM/ESDI driver era. This can
cause the drive components to shrink enough to make the track
marker align with the tracks. We don't see that kind of
platter spindle wear much anymore, but back in the old days,
the balancing and bearings weren't as good. Still, under the
right circumstances, it might help. It would depend on how old
the drive is and how many hours of wear have occurred. You
have to be quick to get your info off the drive when it works.
Back then, the drives were much smaller, so there wasn't so
much to copy. So, go after the important data first.
4. The drive doesn't spin. Either the onboard controller is
bad or the motor is bad (assuming you did try the drive in
another machine). It's time to hit the net and local
independent shops to see if you can locate another drive of
the same make and model that's good. Since the drive is
probably an older drive and no longer in distribution, your
best bet is to find an identical used drive. If you know
someone with the same make and model, you might be wise to try
and persuade them to sell you their drive with an offer of
providing them with a free upgraded drive. If you can locate
an identical drive, start with the controller replacement ...
this is the simplest and least invasive. If swapping the
controller doesn't produce the desire result, you can tear
into the drive and swap the motors. While you have both drive
opened up to accomplish this, scrutinize the platters, heads
and armatures. You might even hook the drive up and power it
from a system with both drives attached. This way, you could
see anything that deviates between the actions of both drives
when they are initialized. Swapping patters is unlikely to
produce any positive result. They are a balanced system like
the tires on your car and I suspect that the balance will be
different for each drive as will other variables.
5. There's always Ontrack Corp. who will attempt to recoup
your info starting at $500 and going up from there. They don't
fix and return the drive either.
If the info is all that important to you, I would seek some
professional and experience technician in your locality who
makes his living from servicing and building computer systems
... not just selling them. If you have had much experience
salvaging information from bad hard drives, your likelihood of
success is low. In the case of soft corruption, all utilities
have their eccentricities. Often times, Norton Disk Doctor
will go too far (if you let it). It's wise to just let those
utilities small steps and then have a look at the drive and
see if you can copy it off. Norton will go so far as to rename
directories and files, and even delete them or break them up
into fragments which are useless.
Mar 14, 2008
How to make the Best Compressing using WinRAR
FIRST What were going to do is to set up your options correctly.
Open WinRAR
OPTIONS | SETTINGS | COMPRESSSION | CREATE DEFAULT
GENERAL | (ok now that we're there, here's what U do next)
But 1st -> realize that everything U set on the default profile will occur everytime U rar files. So if U only need a password occasionally, or other special settings, then create another profile for those purposes. U can change which profile U need to use when WinRar is open. The Default profile is used otherwise, such as when using WinRar from the context menus in explorer.
General tab:
Archive format RAR
Compression method BEST
size (enter in BYTES the size you want as the max single Rar file). I use 51,200,000 (50,000 KB x 1024). But chose yer max size as U wish.
Update method ADD AND REPLACE FILES
Archiving options: check > PUT RECOVERY RECORD
Archiving options: check > TEST ARCHIVED FILES.
Archiving options: check > DELETE FILES AFTER ARCHIVING ( unless U want yer HDD to fill up with the rars & the original files for some reason)
Archiving options: do NOT check > Put authenticy verification, as this can be a source of Error Messages being generated upon extraction.
Archiving options: check > Create SFX ONLY if U don't expect the person getting the filez to have WinRar. Otherwise leave it UNCHECKED.
Archiving options: do NOT check > Create Solid Archive. This can cause problems in certain cases.
Archiving options: do NOT check > Lock Arhive. This has NOTHING to do with a password.
Advanced tab:
Recovery Record -> U can leave it at 1%. Only set it higher if U expect the rar files to have a high risk of corruption. (very bad internet connections, or use on floppy disks, etc)
All else can be left alone. Don't bother with the Compression button.
Files Tab
File Paths -> STORE RELATIVE PATHS. (unless U have a specific folder U want the files to be extracted to. Such as c:\program files\No Name Appz\link catcher).
The rest leave alone
Backup Tab
No need to change anything.
Time Tab
Files to Process -> OF ANY TIME
Comment Tab
Whatever comment U enter there will be shown on the right hand pane when WinRar opens yer Rar files. Think of something fun, catchy,interesting. I always mention that the files have recovery record set, so if they are corrupted in transfer, the person knows to use REPAIR function.
Click OK, U have now created yer default profile.
CREATING a PASSWORD PROFILE, which will NOT be the default:
Open WinRar
Click the ADD Icon
ADVANCED | Push the SET PASSWORD Button
Check the SHOW PASSWORD box, so U can see what U typed and also copy/paste it to wherever U need it, such as on yer post. Now only one box will be open to enter the password. COPY/PASTE it to a txt file. I call mine WinRAR_Password.txt. Do this IMMEDIATELY afer entering it, before closing that window, or U may be very sorry later.
Enter the password. It is CASE SENSITIVE. If the password is 8 or more alpha-numeric characters, no one will be able to hack it. Unless they own a super-computer. Avoid using words that are found in dictionaries.
Check the encrypt file names box. That way, even if some nasty person obtains yer Rar file, they won't know what is in it, especially if the name U give the rar file is "Grandma_pix.rar" or whatever.
Back to GENERAL tab | PROFILES button | Save Current Settings to a New Profile
Enter the name of this profile. For example if the passwd is ht*p://www.superforum.com, U might name the profile Superforum. Only U will see this profile name. It does not go into the rar files made from it.
Do NOTHING more, do NOT set this as default profile.
Click OK | Click OK again.
Now U have a Passworded Profile.
HOW TO USE the PASSWORD PROFILE
Note -> Everything U set on the default profile will occur everytime U rar files. So when U need the password profile, follow these instructions. The Default profile is used otherwise, such as when using WinRar from the contest menus in explorer.
Open WinRar
Browse to the filez/folderz U want to Rar with Password.
Highlight all filez/folderz to be included.
Press the ADD button.
GENERAL tab | PROFILES button
Scoll down to the profile whcih has the password set. In my example Superforum
Click OK
The file are Rar'd. U can check if U did all correctly by opening the rar filez, and seeing if a password is required.
Until U change back to DEFAULT profile in this same method, or close WinRar, all Rar'z U create after this will have a password.
REPAIRING A CORRUPTED RAR FILE:
With Win Explorer create a sub folder REPAIRED
Open WinRar, browse to the folder with the damaged Rar file(z). U can find which one is bad by selecting the 1st RAR file and using TEST button.
Select the damaged file, press REPAIR button.
In dialogue box, enter the path to the REPAIR subfolder, or browse to it.
As long as there is a RECOVERY record in that Rar, it will be repaired.
Copy all the NON-DAMAGED rars to your repair folder and rename the REPAIRED file back to it's original name.
Proceed with extraction in the REPAIR folder as normal.
MISC TIPS:
If U select a folder to Rar, later when U extract it inside that folder, U end up with nested folders of same name. (We've all seen this often when extracting rars.
So Instead, go inside the folder, select all the filez & sub-folderz. Now U have a rar inside just one folder.
Open WinRAR
OPTIONS | SETTINGS | COMPRESSSION | CREATE DEFAULT
GENERAL | (ok now that we're there, here's what U do next)
But 1st -> realize that everything U set on the default profile will occur everytime U rar files. So if U only need a password occasionally, or other special settings, then create another profile for those purposes. U can change which profile U need to use when WinRar is open. The Default profile is used otherwise, such as when using WinRar from the context menus in explorer.
General tab:
Archive format RAR
Compression method BEST
size (enter in BYTES the size you want as the max single Rar file). I use 51,200,000 (50,000 KB x 1024). But chose yer max size as U wish.
Update method ADD AND REPLACE FILES
Archiving options: check > PUT RECOVERY RECORD
Archiving options: check > TEST ARCHIVED FILES.
Archiving options: check > DELETE FILES AFTER ARCHIVING ( unless U want yer HDD to fill up with the rars & the original files for some reason)
Archiving options: do NOT check > Put authenticy verification, as this can be a source of Error Messages being generated upon extraction.
Archiving options: check > Create SFX ONLY if U don't expect the person getting the filez to have WinRar. Otherwise leave it UNCHECKED.
Archiving options: do NOT check > Create Solid Archive. This can cause problems in certain cases.
Archiving options: do NOT check > Lock Arhive. This has NOTHING to do with a password.
Advanced tab:
Recovery Record -> U can leave it at 1%. Only set it higher if U expect the rar files to have a high risk of corruption. (very bad internet connections, or use on floppy disks, etc)
All else can be left alone. Don't bother with the Compression button.
Files Tab
File Paths -> STORE RELATIVE PATHS. (unless U have a specific folder U want the files to be extracted to. Such as c:\program files\No Name Appz\link catcher).
The rest leave alone
Backup Tab
No need to change anything.
Time Tab
Files to Process -> OF ANY TIME
Comment Tab
Whatever comment U enter there will be shown on the right hand pane when WinRar opens yer Rar files. Think of something fun, catchy,interesting. I always mention that the files have recovery record set, so if they are corrupted in transfer, the person knows to use REPAIR function.
Click OK, U have now created yer default profile.
CREATING a PASSWORD PROFILE, which will NOT be the default:
Open WinRar
Click the ADD Icon
ADVANCED | Push the SET PASSWORD Button
Check the SHOW PASSWORD box, so U can see what U typed and also copy/paste it to wherever U need it, such as on yer post. Now only one box will be open to enter the password. COPY/PASTE it to a txt file. I call mine WinRAR_Password.txt. Do this IMMEDIATELY afer entering it, before closing that window, or U may be very sorry later.
Enter the password. It is CASE SENSITIVE. If the password is 8 or more alpha-numeric characters, no one will be able to hack it. Unless they own a super-computer. Avoid using words that are found in dictionaries.
Check the encrypt file names box. That way, even if some nasty person obtains yer Rar file, they won't know what is in it, especially if the name U give the rar file is "Grandma_pix.rar" or whatever.
Back to GENERAL tab | PROFILES button | Save Current Settings to a New Profile
Enter the name of this profile. For example if the passwd is ht*p://www.superforum.com, U might name the profile Superforum. Only U will see this profile name. It does not go into the rar files made from it.
Do NOTHING more, do NOT set this as default profile.
Click OK | Click OK again.
Now U have a Passworded Profile.
HOW TO USE the PASSWORD PROFILE
Note -> Everything U set on the default profile will occur everytime U rar files. So when U need the password profile, follow these instructions. The Default profile is used otherwise, such as when using WinRar from the contest menus in explorer.
Open WinRar
Browse to the filez/folderz U want to Rar with Password.
Highlight all filez/folderz to be included.
Press the ADD button.
GENERAL tab | PROFILES button
Scoll down to the profile whcih has the password set. In my example Superforum
Click OK
The file are Rar'd. U can check if U did all correctly by opening the rar filez, and seeing if a password is required.
Until U change back to DEFAULT profile in this same method, or close WinRar, all Rar'z U create after this will have a password.
REPAIRING A CORRUPTED RAR FILE:
With Win Explorer create a sub folder REPAIRED
Open WinRar, browse to the folder with the damaged Rar file(z). U can find which one is bad by selecting the 1st RAR file and using TEST button.
Select the damaged file, press REPAIR button.
In dialogue box, enter the path to the REPAIR subfolder, or browse to it.
As long as there is a RECOVERY record in that Rar, it will be repaired.
Copy all the NON-DAMAGED rars to your repair folder and rename the REPAIRED file back to it's original name.
Proceed with extraction in the REPAIR folder as normal.
MISC TIPS:
If U select a folder to Rar, later when U extract it inside that folder, U end up with nested folders of same name. (We've all seen this often when extracting rars.
So Instead, go inside the folder, select all the filez & sub-folderz. Now U have a rar inside just one folder.
Mar 5, 2008
How to Securely Configure a FTP Server(BulletProof)
I am not sure where I found this tutorial, It’s been a while…It might even have been here... ..So if it is one of yours, my hat goes off to you once again....
After reading the excellent tutorial on "Creating an FTP" that Norway posted…
(I would suggest reading and following his tutorial first, then following up with this one)
I thought that perhaps this tutorial might be pretty helpful for those interested in knowing how to configure their Bulletproof FTP Server that don't already know how... Here's how to get started…
This is for the BulletProof FTP Server 2.10. However, It should work fine on most following versions as well.
I'm assuming you have it installed.
Basics
1. Start the program.
2. Click on Setup > Main > General from the pull-down menu.
3. Enter your server name into the 'Server Name' box. Under Connection set the “Max number of users" to any number. This is the limit as to how many users can be on your sever at any time.
4. Click on the 'options' tab of that same panel (on the side)
5. Look at the bottom, under IP Options. Put a check in the box “Refuse Multiple Connections from the same IP”. This will prevent one person from blocking your FTP to others.
6. Also put a check in the 'Blocked Banned IP (instead of notifying client). VERY IMPORTANT! If somebody decides to 'Hammer' (attempt to login numerous times VERY quickly) your server/computer may CRASH if you don't enable this.
7. Click on the 'advanced' tab
8. At the bottom again look at the 'hammering area'
9. Enable 'anti-hammer' and 'do not reply to people hammering' Set it for the following: Block IP 120 min if 5 connections in 60 sec. You can set this at whatever you want to but that is pretty much a standard Click 'OK'
Adding Users
11. Setup > User accounts form pull-down.
12. Right click in the empty 'User Accounts' area on the right: choose 'Add'
13. Enter account name. (ie: logon name)
14. In the 'Access rights' box right click: choose ‘Add’.
15. Browse until you find the directory (folder) you want to share. In the right column you will see a bunch of checkboxes. Put a check in the following ones: Read, Write, Append, Make, List, and +Subdirs. Press 'select'.
16. Enter a password for your new FTP account.
17. Click on 'Miscellaneous' in the left column. Make sure 'Enable Account' is selected. Enable 'Max Number of Users' set it at a number other than zero. 1 for a personal account and more that one for a group account. Enable 'Max. no. of connects per IP' set it at 1
18. Under 'Files' enable 'show relative path' this is a security issue. A FTP client will now not be able to see the ENTIRE path of the FTP. It will only see the path from the main directory. Hide hidden flies as well.
Put a tick in both of these.
Advanced:
You don't need to do any of this stuff, but It will help tweak your server and help you maintain order on it. All of the following will be broken down into small little areas that will tell you how to do one thing at a time.
Changing the Port
The default port is always 21, but you can change this. Many ISPs will routinely do a scan of its own users to find a ftp server, also when people scan for pubs they may scan your IP, thus finding your ftp server. If you do decide to change it many suggest that you make the port over 10,000.
1. Setup > Main > General
2. In the 'Connection' Area is a setting labeled 'Listen on Port Number:'
3. Make it any number you want. That will be your port number.
4. Click 'OK'
Making an 'Upload Only' or 'Download Only' ftp server.
This is for the entire SERVER, not just a user.
1. Setup > Main > Advanced
2. In the advanced window you will have the following options: uploads and downloads, downloads only, and uploads only. By default upload and download will be checked. Change it to whatever you want.
3. Click 'OK’
While you are running your server, usually you will end up spending more time at your computer than you normally do. Don't be afraid to ban IP's. Remember, on your FTP you do as you want.
When you are online you must also select the open server button next to the on-line button which is the on-line Button
You also have to use the actual Numbered ip Address ie: 66.250.216.67
Or even Better yet, get a no-ip.com address
After reading the excellent tutorial on "Creating an FTP" that Norway posted…
(I would suggest reading and following his tutorial first, then following up with this one)
I thought that perhaps this tutorial might be pretty helpful for those interested in knowing how to configure their Bulletproof FTP Server that don't already know how... Here's how to get started…
This is for the BulletProof FTP Server 2.10. However, It should work fine on most following versions as well.
I'm assuming you have it installed.
Basics
1. Start the program.
2. Click on Setup > Main > General from the pull-down menu.
3. Enter your server name into the 'Server Name' box. Under Connection set the “Max number of users" to any number. This is the limit as to how many users can be on your sever at any time.
4. Click on the 'options' tab of that same panel (on the side)
5. Look at the bottom, under IP Options. Put a check in the box “Refuse Multiple Connections from the same IP”. This will prevent one person from blocking your FTP to others.
6. Also put a check in the 'Blocked Banned IP (instead of notifying client). VERY IMPORTANT! If somebody decides to 'Hammer' (attempt to login numerous times VERY quickly) your server/computer may CRASH if you don't enable this.
7. Click on the 'advanced' tab
8. At the bottom again look at the 'hammering area'
9. Enable 'anti-hammer' and 'do not reply to people hammering' Set it for the following: Block IP 120 min if 5 connections in 60 sec. You can set this at whatever you want to but that is pretty much a standard Click 'OK'
Adding Users
11. Setup > User accounts form pull-down.
12. Right click in the empty 'User Accounts' area on the right: choose 'Add'
13. Enter account name. (ie: logon name)
14. In the 'Access rights' box right click: choose ‘Add’.
15. Browse until you find the directory (folder) you want to share. In the right column you will see a bunch of checkboxes. Put a check in the following ones: Read, Write, Append, Make, List, and +Subdirs. Press 'select'.
16. Enter a password for your new FTP account.
17. Click on 'Miscellaneous' in the left column. Make sure 'Enable Account' is selected. Enable 'Max Number of Users' set it at a number other than zero. 1 for a personal account and more that one for a group account. Enable 'Max. no. of connects per IP' set it at 1
18. Under 'Files' enable 'show relative path' this is a security issue. A FTP client will now not be able to see the ENTIRE path of the FTP. It will only see the path from the main directory. Hide hidden flies as well.
Put a tick in both of these.
Advanced:
You don't need to do any of this stuff, but It will help tweak your server and help you maintain order on it. All of the following will be broken down into small little areas that will tell you how to do one thing at a time.
Changing the Port
The default port is always 21, but you can change this. Many ISPs will routinely do a scan of its own users to find a ftp server, also when people scan for pubs they may scan your IP, thus finding your ftp server. If you do decide to change it many suggest that you make the port over 10,000.
1. Setup > Main > General
2. In the 'Connection' Area is a setting labeled 'Listen on Port Number:'
3. Make it any number you want. That will be your port number.
4. Click 'OK'
Making an 'Upload Only' or 'Download Only' ftp server.
This is for the entire SERVER, not just a user.
1. Setup > Main > Advanced
2. In the advanced window you will have the following options: uploads and downloads, downloads only, and uploads only. By default upload and download will be checked. Change it to whatever you want.
3. Click 'OK’
While you are running your server, usually you will end up spending more time at your computer than you normally do. Don't be afraid to ban IP's. Remember, on your FTP you do as you want.
When you are online you must also select the open server button next to the on-line button which is the on-line Button
You also have to use the actual Numbered ip Address ie: 66.250.216.67
Or even Better yet, get a no-ip.com address
Mar 2, 2008
How to Repair Winsock 2
These guide will show you how to repair Winsock 2. Well as you might or might not know the symptoms when Winsock2 is damaged show when you try to release and renew the IP address using IPCONFIG...
And you get the following error message:
An error occurred while renewing interface 'Internet': An operation was attempted on something that is not a socket.
Also Internet Explorer may give the following error message:
The page cannot be displayed Additionally, you may have no IP address or no Automatic Private IP Addressing (APIPA) address, and you may be receiving IP packets but not sending them.
There are two easy ways to determine if Winsock2 is damaged:
From the XP source files, go to the Support / Tools directory
Winsock Test Method 1
Run netdiag /test:winsock
The end should say Winsock test ..... passed
Winsock Test Method 2
Run Msinfo32
Click on the + by Components
Click on the by Network
Click on Protocol
There should be 10 sections if the Winsock2 key is ok
MSAFD Tcpip [TCP/IP]
MSAFD Tcpip [UDP/IP]
RSVP UDP Service Provider
RSVP TCP Service Provider
MSAFD NetBIOS [\Device\NetBT_Tcpip...
MSAFD NetBIOS [\Device\NetBT_Tcpip...
MSAFD NetBIOS [\Device\NetBT_Tcpip...
MSAFD NetBIOS [\Device\NetBT_Tcpip...
MSAFD NetBIOS [\Device\NetBT_Tcpip...
MSAFD NetBIOS [\Device\NetBT_Tcpip...
If the names are anything different from those in this list, then likely Winsock2 is corrupted and needs to be repaired.
If you have any 3rd party software installed, the name MSAFD may be changed.
There should be no fewer than 10 sections.
To repair Winsock2
Run Regedit
Delete the following two registry keys:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Winsock
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Winsock2
Restart the computer
Go to Network Connections
Right click and select Properties
Click on the Install button
Select Protocol
Click on the Add button
Click on the Have Disk button
Browse to the \Windows\inf directory
Click on the Open button
Click on the OK button
Highlight Internet Protocol (TCP/IP)
Click on the OK button
Reboot (Don't forget)
Do contact me if you have any Problem.
And you get the following error message:
An error occurred while renewing interface 'Internet': An operation was attempted on something that is not a socket.
Also Internet Explorer may give the following error message:
The page cannot be displayed Additionally, you may have no IP address or no Automatic Private IP Addressing (APIPA) address, and you may be receiving IP packets but not sending them.
There are two easy ways to determine if Winsock2 is damaged:
From the XP source files, go to the Support / Tools directory
Winsock Test Method 1
Run netdiag /test:winsock
The end should say Winsock test ..... passed
Winsock Test Method 2
Run Msinfo32
Click on the + by Components
Click on the by Network
Click on Protocol
There should be 10 sections if the Winsock2 key is ok
MSAFD Tcpip [TCP/IP]
MSAFD Tcpip [UDP/IP]
RSVP UDP Service Provider
RSVP TCP Service Provider
MSAFD NetBIOS [\Device\NetBT_Tcpip...
MSAFD NetBIOS [\Device\NetBT_Tcpip...
MSAFD NetBIOS [\Device\NetBT_Tcpip...
MSAFD NetBIOS [\Device\NetBT_Tcpip...
MSAFD NetBIOS [\Device\NetBT_Tcpip...
MSAFD NetBIOS [\Device\NetBT_Tcpip...
If the names are anything different from those in this list, then likely Winsock2 is corrupted and needs to be repaired.
If you have any 3rd party software installed, the name MSAFD may be changed.
There should be no fewer than 10 sections.
To repair Winsock2
Run Regedit
Delete the following two registry keys:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Winsock
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Winsock2
Restart the computer
Go to Network Connections
Right click and select Properties
Click on the Install button
Select Protocol
Click on the Add button
Click on the Have Disk button
Browse to the \Windows\inf directory
Click on the Open button
Click on the OK button
Highlight Internet Protocol (TCP/IP)
Click on the OK button
Reboot (Don't forget)
Do contact me if you have any Problem.
Feb 28, 2008
BIOS Update Guide/Procedure
All latest Motherboards today, 486/ Pentium / Pentium Pro etc.,ensure that upgrades are easily obtained by incorporating the system BIOS in a FLASH Memory component. With FLASH BIOS, there is no need to replace an EPROM component. Once downloaded, the upgrade utility fits on a floppy disc allowing the user to save, verify and update the system BIOS. A hard drive or a network drive can also be used to run the newer upgrade utilities. However, memory managers can not be installed while upgrading.
Most pre-Pentium motherboards do not have a Flash BIOS. The following instructions therefore do not apply to these boards. If your motherboard does not have a Flash BIOS (EEPROM) you will need to use an EPROM programmer to re-program the BIOS chip. See your dealer for more information about this.
Please read the following instructions in full before starting a Flash BIOS upgrade:
A. Create a Bootable Floppy (in DOS)
•With a non-formatted disk, type the following:
format a:/s
•If using a formatted disk, type:
sys a:
This procedure will ensure a clean boot when you are flashing the new BIOS.
B. Download the BIOS file
•Download the correct BIOS file by clicking on the file name of the BIOS file you wish to download.
•Save the BIOS file and the Flash Utility file in the boot disk you have created. Unzip the BIOS file and the flash utility file. If you don't have an "unzip" utility, download the WinZip for Windows 95 shareware/ evaluation copy for that one time use from _www.winzip.com or _www.pkware.com. Most CD ROMs found in computer magazines, have a shareware version of WinZip on them.
•You should have extracted two files:
Flash BIOS utility eg: flash7265.exe (for example)
BIOS eg: 6152J900.bin (example)
Use the latest flash utility available unless otherwise specified (either on the BIOS update page or in the archive file). This information is usually provided.
C. Upgrade the System BIOS
During boot up, write down the old BIOS version because you will need to use it for the BIOS backup file name.
Place the bootable floppy disk containing the BIOS file and the Flash Utility in drive a, and reboot the system in MS-DOS, preferably Version 6.22
•At the A:> prompt, type the corresponding Flash BIOS utility and the BIOS file with its extension.
For example:
flash625 615j900.bin
•From the Flash Memory Writer menu, select "Y" to "Do you want to save BIOS?" if you want to save (back up) your current BIOS (strongly recommended), then type the name of your current BIOS and its extension after FILE NAME TO SAVE: eg: a:\613J900.bin
Alternatively select "N" if you don't want to save your current BIOS. Beware, though, that you won't be able to recover from a possible failure.
•Select "Y" to "Are you sure to program?"
•Wait until it displays "Message: Power Off or Reset the system"
Once the BIOS has been successfully loaded, remove the floppy disk and reboot the system. If you write to BIOS but cannot complete the procedure, do not switch off, because the computer will not be able to boo, and you will not be given another chance to flash. In this case leave your system on until you resolve the problem (flashing BIOS with old file is a possible solution, provided you've made a backup before)
Make sure the new BIOS version has been loaded properly by taking note of the BIOS identifier as the system is rebooting.
For AMI BIOS
Once the BIOS has been successfully loaded, remove the floppy disk and reboot the system holding the "END" key prior to power on until you enter CMOS setup. If you do not do this the first time booting up after upgrading the BIOS, the system will hang.
BIOS Update Tips
note:
1.Make sure never to turn off or reset your computer during the flash process. This will corrupt the BIOS data. We also recommend that you make a copy of your current BIOS on the bootable floppy so you can reflash it if you need to. (This option is not available when flashing an AMI BIOS).
2. If you have problems installing your new BIOS please check the following:
Have you done a clean boot?
In other words, did you follow the above procedure for making a bootable floppy? This ensures that when booting from "A" there are no device drivers on the diskette. Failing to do a clean boot is the most common cause for getting a "Memory Insufficient" error message when attempting to flash a BIOS.
If you have not used a bootable floppy, insure a clean boot either by
a) pressing F5 during bootup
b) by removing all device drivers on the CONFIG.SYS including the HIMEM.SYS. Do this by using the EDIT command.
Have you booted up under DOS?
Booting in Windows is another common cause for getting a "Memory Insufficient" error message when attempting to flash a BIOS. Make sure to boot up to DOS with a minimum set of drivers. Important: Booting in DOS does not mean selecting "Restart computer in MS-DOS Mode" from Windows98/95 shutdown menu or going to Prompt mode in WindowsNT, but rather following the above procedure (format a: /s and rebooting from a:\).
Have you entered the full file name of the flash utility and the BIOS plus its extension?
Do not forget that often you will need to add a drive letter (a:\) before flashing the BIOS. Example: when asked for file name of new BIOS file which is on your floppy disk, in case you're working from c:\ your will need to type a:\615j900.bin, rather than 615j900.bin only.
Most pre-Pentium motherboards do not have a Flash BIOS. The following instructions therefore do not apply to these boards. If your motherboard does not have a Flash BIOS (EEPROM) you will need to use an EPROM programmer to re-program the BIOS chip. See your dealer for more information about this.
Please read the following instructions in full before starting a Flash BIOS upgrade:
A. Create a Bootable Floppy (in DOS)
•With a non-formatted disk, type the following:
format a:/s
•If using a formatted disk, type:
sys a:
This procedure will ensure a clean boot when you are flashing the new BIOS.
B. Download the BIOS file
•Download the correct BIOS file by clicking on the file name of the BIOS file you wish to download.
•Save the BIOS file and the Flash Utility file in the boot disk you have created. Unzip the BIOS file and the flash utility file. If you don't have an "unzip" utility, download the WinZip for Windows 95 shareware/ evaluation copy for that one time use from _www.winzip.com or _www.pkware.com. Most CD ROMs found in computer magazines, have a shareware version of WinZip on them.
•You should have extracted two files:
Flash BIOS utility eg: flash7265.exe (for example)
BIOS eg: 6152J900.bin (example)
Use the latest flash utility available unless otherwise specified (either on the BIOS update page or in the archive file). This information is usually provided.
C. Upgrade the System BIOS
During boot up, write down the old BIOS version because you will need to use it for the BIOS backup file name.
Place the bootable floppy disk containing the BIOS file and the Flash Utility in drive a, and reboot the system in MS-DOS, preferably Version 6.22
•At the A:> prompt, type the corresponding Flash BIOS utility and the BIOS file with its extension.
For example:
flash625 615j900.bin
•From the Flash Memory Writer menu, select "Y" to "Do you want to save BIOS?" if you want to save (back up) your current BIOS (strongly recommended), then type the name of your current BIOS and its extension after FILE NAME TO SAVE: eg: a:\613J900.bin
Alternatively select "N" if you don't want to save your current BIOS. Beware, though, that you won't be able to recover from a possible failure.
•Select "Y" to "Are you sure to program?"
•Wait until it displays "Message: Power Off or Reset the system"
Once the BIOS has been successfully loaded, remove the floppy disk and reboot the system. If you write to BIOS but cannot complete the procedure, do not switch off, because the computer will not be able to boo, and you will not be given another chance to flash. In this case leave your system on until you resolve the problem (flashing BIOS with old file is a possible solution, provided you've made a backup before)
Make sure the new BIOS version has been loaded properly by taking note of the BIOS identifier as the system is rebooting.
For AMI BIOS
Once the BIOS has been successfully loaded, remove the floppy disk and reboot the system holding the "END" key prior to power on until you enter CMOS setup. If you do not do this the first time booting up after upgrading the BIOS, the system will hang.
BIOS Update Tips
note:
1.Make sure never to turn off or reset your computer during the flash process. This will corrupt the BIOS data. We also recommend that you make a copy of your current BIOS on the bootable floppy so you can reflash it if you need to. (This option is not available when flashing an AMI BIOS).
2. If you have problems installing your new BIOS please check the following:
Have you done a clean boot?
In other words, did you follow the above procedure for making a bootable floppy? This ensures that when booting from "A" there are no device drivers on the diskette. Failing to do a clean boot is the most common cause for getting a "Memory Insufficient" error message when attempting to flash a BIOS.
If you have not used a bootable floppy, insure a clean boot either by
a) pressing F5 during bootup
b) by removing all device drivers on the CONFIG.SYS including the HIMEM.SYS. Do this by using the EDIT command.
Have you booted up under DOS?
Booting in Windows is another common cause for getting a "Memory Insufficient" error message when attempting to flash a BIOS. Make sure to boot up to DOS with a minimum set of drivers. Important: Booting in DOS does not mean selecting "Restart computer in MS-DOS Mode" from Windows98/95 shutdown menu or going to Prompt mode in WindowsNT, but rather following the above procedure (format a: /s and rebooting from a:\).
Have you entered the full file name of the flash utility and the BIOS plus its extension?
Do not forget that often you will need to add a drive letter (a:\) before flashing the BIOS. Example: when asked for file name of new BIOS file which is on your floppy disk, in case you're working from c:\ your will need to type a:\615j900.bin, rather than 615j900.bin only.
Feb 21, 2008
Ever wonder what does DirectX means? Well..
Ever wondered just what that enigmatic name means?
Gaming and multimedia applications are some of the most satisfying programs you can get for your PC, but getting them to run properly isn’t always as easy as it could be. First, the PC architecture was never designed as a gaming platform. Second, the wide-ranging nature of the PC means that one person’s machine can be different from another. While games consoles all contain the same hardware, PCs don’t: the massive range of difference can make gaming a headache.
To alleviate as much of the pain as possible, Microsoft needed to introduce a common standard which all games and multimedia applications could follow – a common interface between the OS and whatever hardware is installed in the PC, if you like. This common interface is DirectX, something which can be the source of much confusion.
DirectX is an interface designed to make certain programming tasks much easier, for both the game developer and the rest of us who just want to sit down and play the latest blockbuster. Before we can explain what DirectX is and how it works though, we need a little history lesson.
DirectX history
Any game needs to perform certain tasks again and again. It needs to watch for your input from mouse, joystick or keyboard, and it needs to be able to display screen images and play sounds or music. That’s pretty much any game at the most simplistic level.
Imagine how incredibly complex this was for programmers developing on the early pre-Windows PC architecture, then. Each programmer needed to develop their own way of reading the keyboard or detecting whether a joystick was even attached, let alone being used to play the game. Specific routines were needed even to display the simplest of images on the screen or play a simple sound.
Essentially, the game programmers were talking directly to your PC’s hardware at a fundamental level. When Microsoft introduced Windows, it was imperative for the stability and success of the PC platform that things were made easier for both the developer and the player. After all, who would bother writing games for a machine when they had to reinvent the wheel every time they began work on a new game? Microsoft’s idea was simple: stop programmers talking directly to the hardware, and build a common toolkit which they could use instead. DirectX was born.
How it works
At the most basic level, DirectX is an interface between the hardware in your PC and Windows itself, part of the Windows API or Application Programming Interface. Let’s look at a practical example. When a game developer wants to play a sound file, it’s simply a case of using the correct library function. When the game runs, this calls the DirectX API, which in turn plays the sound file. The developer doesn’t need to know what type of sound card he’s dealing with, what it’s capable of, or how to talk to it. Microsoft has provided DirectX, and the sound card manufacturer has provided a DirectX-capable driver. He asks for the sound to be played, and it is – whichever machine it runs on.
From our point of view as gamers, DirectX also makes things incredibly easy – at least in theory. You install a new sound card in place of your old one, and it comes with a DirectX driver. Next time you play your favourite game you can still hear sounds and music, and you haven’t had to make any complex configuration changes.
Originally, DirectX began life as a simple toolkit: early hardware was limited and only the most basic graphical functions were required. As hardware and software has evolved in complexity, so has DirectX. It’s now much more than a graphical toolkit, and the term has come to encompass a massive selection of routines which deal with all sorts of hardware communication. For example, the DirectInput routines can deal with all sorts of input devices, from simple two-button mice to complex flight joysticks. Other parts include DirectSound for audio devices and DirectPlay provides a toolkit for online or multiplayer gaming.
DirectX versions
The current version of DirectX at time of writing is DirectX 9.0. This runs on all versions of Windows from Windows 98 up to and including Windows Server 2003 along with every revision in between. It doesn’t run on Windows 95 though: if you have a machine with Windows 95 installed, you’re stuck with the older and less capable 8.0a. Windows NT 4 also requires a specific version – in this case, it’s DirectX 3.0a.
With so many versions of DirectX available over the years, it becomes difficult to keep track of which version you need. In all but the most rare cases, all versions of DirectX are backwardly compatible – games which say they require DirectX 7 will happily run with more recent versions, but not with older copies. Many current titles explicitly state that they require DirectX 9, and won’t run without the latest version installed. This is because they make use of new features introduced with this version, although it has been known for lazy developers to specify the very latest version as a requirement when the game in question doesn’t use any of the new enhancements. Generally speaking though, if a title is version locked like this, you will need to upgrade before you can play. Improvements to the core DirectX code mean you may even see improvements in many titles when you upgrade to the latest build of DirectX. Downloading and installing DirectX need not be complex, either.
Upgrading DirectX
All available versions of Windows come with DirectX in one form or another as a core system component which cannot be removed, so you should always have at least a basic implementation of the system installed on your PC. However, many new games require the very latest version before they work properly, or even at all.
Generally, the best place to install the latest version of DirectX from is the dedicated section of the Microsoft Web site, which is found at www.microsoft.com/windows/directx. As we went to press, the most recent build available for general download was DirectX 9.0b. You can download either a simple installer which will in turn download the components your system requires as it installs, or download the complete distribution package in one go for later offline installation.
Another good source for DirectX is games themselves. If a game requires a specific version, it’ll be on the installation CD and may even be installed automatically by the game’s installer itself. You won’t find it on magazine cover discs though, thanks to Microsoft’s licensing terms.
Diagnosing problems
Diagnosing problems with a DirectX installation can be problematic, especially if you don’t know which one of the many components is causing your newly purchased game to fall over. Thankfully, Microsoft provides a useful utility called the DirectX Diagnostic Tool, although this isn’t made obvious. You won’t find this tool in the Start Menu with any version of Windows, and each tends to install it in a different place.
The easiest way to use it is to open the Start Menu’s Run dialog, type in dxdiag and then click OK. When the application first loads, it takes a few seconds to interrogate your DirectX installation and find any problems. First, the DirectX Files tab displays version information on each one of the files your installation uses. The Notes section at the bottom is worth checking, as missing or corrupted files will be flagged here.
The tabs marked Display, Sound, Music, Input and Network all relate to specific areas of DirectX, and all but the Input tab provide tools to test the correct functioning on your hardware. Finally, the More Help tab provides a useful way to start the DirectX Troubleshooter, Microsoft’s simple linear problem solving tool for many common DirectX issues.
Gaming and multimedia applications are some of the most satisfying programs you can get for your PC, but getting them to run properly isn’t always as easy as it could be. First, the PC architecture was never designed as a gaming platform. Second, the wide-ranging nature of the PC means that one person’s machine can be different from another. While games consoles all contain the same hardware, PCs don’t: the massive range of difference can make gaming a headache.
To alleviate as much of the pain as possible, Microsoft needed to introduce a common standard which all games and multimedia applications could follow – a common interface between the OS and whatever hardware is installed in the PC, if you like. This common interface is DirectX, something which can be the source of much confusion.
DirectX is an interface designed to make certain programming tasks much easier, for both the game developer and the rest of us who just want to sit down and play the latest blockbuster. Before we can explain what DirectX is and how it works though, we need a little history lesson.
DirectX history
Any game needs to perform certain tasks again and again. It needs to watch for your input from mouse, joystick or keyboard, and it needs to be able to display screen images and play sounds or music. That’s pretty much any game at the most simplistic level.
Imagine how incredibly complex this was for programmers developing on the early pre-Windows PC architecture, then. Each programmer needed to develop their own way of reading the keyboard or detecting whether a joystick was even attached, let alone being used to play the game. Specific routines were needed even to display the simplest of images on the screen or play a simple sound.
Essentially, the game programmers were talking directly to your PC’s hardware at a fundamental level. When Microsoft introduced Windows, it was imperative for the stability and success of the PC platform that things were made easier for both the developer and the player. After all, who would bother writing games for a machine when they had to reinvent the wheel every time they began work on a new game? Microsoft’s idea was simple: stop programmers talking directly to the hardware, and build a common toolkit which they could use instead. DirectX was born.
How it works
At the most basic level, DirectX is an interface between the hardware in your PC and Windows itself, part of the Windows API or Application Programming Interface. Let’s look at a practical example. When a game developer wants to play a sound file, it’s simply a case of using the correct library function. When the game runs, this calls the DirectX API, which in turn plays the sound file. The developer doesn’t need to know what type of sound card he’s dealing with, what it’s capable of, or how to talk to it. Microsoft has provided DirectX, and the sound card manufacturer has provided a DirectX-capable driver. He asks for the sound to be played, and it is – whichever machine it runs on.
From our point of view as gamers, DirectX also makes things incredibly easy – at least in theory. You install a new sound card in place of your old one, and it comes with a DirectX driver. Next time you play your favourite game you can still hear sounds and music, and you haven’t had to make any complex configuration changes.
Originally, DirectX began life as a simple toolkit: early hardware was limited and only the most basic graphical functions were required. As hardware and software has evolved in complexity, so has DirectX. It’s now much more than a graphical toolkit, and the term has come to encompass a massive selection of routines which deal with all sorts of hardware communication. For example, the DirectInput routines can deal with all sorts of input devices, from simple two-button mice to complex flight joysticks. Other parts include DirectSound for audio devices and DirectPlay provides a toolkit for online or multiplayer gaming.
DirectX versions
The current version of DirectX at time of writing is DirectX 9.0. This runs on all versions of Windows from Windows 98 up to and including Windows Server 2003 along with every revision in between. It doesn’t run on Windows 95 though: if you have a machine with Windows 95 installed, you’re stuck with the older and less capable 8.0a. Windows NT 4 also requires a specific version – in this case, it’s DirectX 3.0a.
With so many versions of DirectX available over the years, it becomes difficult to keep track of which version you need. In all but the most rare cases, all versions of DirectX are backwardly compatible – games which say they require DirectX 7 will happily run with more recent versions, but not with older copies. Many current titles explicitly state that they require DirectX 9, and won’t run without the latest version installed. This is because they make use of new features introduced with this version, although it has been known for lazy developers to specify the very latest version as a requirement when the game in question doesn’t use any of the new enhancements. Generally speaking though, if a title is version locked like this, you will need to upgrade before you can play. Improvements to the core DirectX code mean you may even see improvements in many titles when you upgrade to the latest build of DirectX. Downloading and installing DirectX need not be complex, either.
Upgrading DirectX
All available versions of Windows come with DirectX in one form or another as a core system component which cannot be removed, so you should always have at least a basic implementation of the system installed on your PC. However, many new games require the very latest version before they work properly, or even at all.
Generally, the best place to install the latest version of DirectX from is the dedicated section of the Microsoft Web site, which is found at www.microsoft.com/windows/directx. As we went to press, the most recent build available for general download was DirectX 9.0b. You can download either a simple installer which will in turn download the components your system requires as it installs, or download the complete distribution package in one go for later offline installation.
Another good source for DirectX is games themselves. If a game requires a specific version, it’ll be on the installation CD and may even be installed automatically by the game’s installer itself. You won’t find it on magazine cover discs though, thanks to Microsoft’s licensing terms.
Diagnosing problems
Diagnosing problems with a DirectX installation can be problematic, especially if you don’t know which one of the many components is causing your newly purchased game to fall over. Thankfully, Microsoft provides a useful utility called the DirectX Diagnostic Tool, although this isn’t made obvious. You won’t find this tool in the Start Menu with any version of Windows, and each tends to install it in a different place.
The easiest way to use it is to open the Start Menu’s Run dialog, type in dxdiag and then click OK. When the application first loads, it takes a few seconds to interrogate your DirectX installation and find any problems. First, the DirectX Files tab displays version information on each one of the files your installation uses. The Notes section at the bottom is worth checking, as missing or corrupted files will be flagged here.
The tabs marked Display, Sound, Music, Input and Network all relate to specific areas of DirectX, and all but the Input tab provide tools to test the correct functioning on your hardware. Finally, the More Help tab provides a useful way to start the DirectX Troubleshooter, Microsoft’s simple linear problem solving tool for many common DirectX issues.
Create One-Click Shutdown and Reboot Shortcuts
First, create a shortcut on your desktop by right-clicking on the desktop, choosing New, and then choosing Shortcut. The Create Shortcut Wizard appears. In the box asking for the location of the shortcut, type shutdown. After you create the shortcut, double-clicking on it will shut down your PC.
But you can do much more with a shutdown shortcut than merely shut down your PC. You can add any combination of several switches to do extra duty, like this:
shutdown -r -t 01 -c "Rebooting your PC"
Double-clicking on that shortcut will reboot your PC after a one-second delay and display the message "Rebooting your PC." The shutdown command includes a variety of switches you can use to customize it. Table 1-3 lists all of them and describes their use.
I use this technique to create two shutdown shortcuts on my desktop—one for turning off my PC, and one for rebooting. Here are the ones I use:
shutdown -s -t 03 -c "Bye Bye m8!"
shutdown -r -t 03 -c "Ill be back m8 ;)!"
Switch
What it does
-s
Shuts down the PC.
-l
Logs off the current user.
-t nn
Indicates the duration of delay, in seconds, before performing the action.
-c "messagetext"
Displays a message in the System Shutdown window. A maximum of 127 characters can be used. The message must be enclosed in quotation marks.
-f
Forces any running applications to shut down.
-r
Reboots the PC.
But you can do much more with a shutdown shortcut than merely shut down your PC. You can add any combination of several switches to do extra duty, like this:
shutdown -r -t 01 -c "Rebooting your PC"
Double-clicking on that shortcut will reboot your PC after a one-second delay and display the message "Rebooting your PC." The shutdown command includes a variety of switches you can use to customize it. Table 1-3 lists all of them and describes their use.
I use this technique to create two shutdown shortcuts on my desktop—one for turning off my PC, and one for rebooting. Here are the ones I use:
shutdown -s -t 03 -c "Bye Bye m8!"
shutdown -r -t 03 -c "Ill be back m8 ;)!"
Switch
What it does
-s
Shuts down the PC.
-l
Logs off the current user.
-t nn
Indicates the duration of delay, in seconds, before performing the action.
-c "messagetext"
Displays a message in the System Shutdown window. A maximum of 127 characters can be used. The message must be enclosed in quotation marks.
-f
Forces any running applications to shut down.
-r
Reboots the PC.
Keyboard, Run, IE, Windows Explorer Shortcut Command
Getting used to using your keyboard exclusively and leaving your mouse behind will make you much more efficient at performing any task on any Windows system.
I use the following keyboard shortcuts every day:
Windows key + R = Run menu
This is usually followed by:
cmd = Command Prompt
iexplore + "web address" = Internet Explorer
compmgmt.msc = Computer Management
dhcpmgmt.msc = DHCP Management
dnsmgmt.msc = DNS Management
services.msc = Services
eventvwr = Event Viewer
dsa.msc = Active Directory Users and Computers
dssite.msc = Active Directory Sites and Services
Windows key + E = Explorer
ALT + Tab = Switch between windows
ALT, Space, X = Maximize window
CTRL + Shift + Esc = Task Manager
Windows key + Break = System properties
Windows key + F = Search
Windows key + D = Hide/Display all windows
CTRL + C = copy
CTRL + X = cut
CTRL + V = paste
Also don't forget about the "Right-click" key next to the right Windows key on your keyboard. Using the arrows and that key can get just about anything done once you've opened up any program.
Keyboard Shortcuts
[Alt] and [Esc] Switch between running applications
[Alt] and letter Select menu item by underlined letter
[Ctrl] and [Esc] Open Program Menu
[Ctrl] and [F4] Close active document or group windows (does not work with some applications)
[Alt] and [F4] Quit active application or close current window
[Alt] and [-] Open Control menu for active document
Ctrl] Lft., Rt. arrow Move cursor forward or back one word
Ctrl] Up, Down arrow Move cursor forward or back one paragraph
[F1] Open Help for active application
Windows+M Minimize all open windows
Shift+Windows+M Undo minimize all open windows
Windows+F1 Open Windows Help
Windows+Tab Cycle through the Taskbar buttons
Windows+Break Open the System Properties dialog box
Accessibility Shortcuts
Right SHIFT for eight seconds........ Switch FilterKeys on and off.
Left ALT +left SHIFT +PRINT SCREEN....... Switch High Contrast on and off.
Left ALT +left SHIFT +NUM LOCK....... Switch MouseKeys on and off.
SHIFT....... five times Switch StickyKeys on and off.
NUM LOCK...... for five seconds Switch ToggleKeys on and off.
Explorer Shortcuts
END....... Display the bottom of the active window.
HOME....... Display the top of the active window.
NUM LOCK+ASTERISK....... on numeric keypad (*) Display all subfolders under the selected folder.
NUM LOCK+PLUS SIGN....... on numeric keypad (+) Display the contents of the selected folder.
NUM LOCK+MINUS SIGN....... on numeric keypad (-) Collapse the selected folder.
LEFT ARROW...... Collapse current selection if it's expanded, or select parent folder.
RIGHT ARROW....... Display current selection if it's collapsed, or select first subfolder.
Type the following commands in your Run Box (Windows Key + R) or Start Run
devmgmt.msc = Device Manager
msinfo32 = System Information
cleanmgr = Disk Cleanup
ntbackup = Backup or Restore Wizard (Windows Backup Utility)
mmc = Microsoft Management Console
excel = Microsoft Excel (If Installed)
msaccess = Microsoft Access (If Installed)
powerpnt = Microsoft PowerPoint (If Installed)
winword = Microsoft Word (If Installed)
frontpg = Microsoft FrontPage (If Installed)
notepad = Notepad
wordpad = WordPad
calc = Calculator
msmsgs = Windows Messenger
mspaint = Microsoft Paint
wmplayer = Windows Media Player
rstrui = System Restore
netscp6 = Netscape 6.x
netscp = Netscape 7.x
netscape = Netscape 4.x
waol = America Online
control = Opens the Control Panel
control printers = Opens the Printers Dialog
Internet Browser
Type in Your address "google", then press
[CTRL] and [Enter] This will add http://www. and .com to & after the word Google
[SHIFT] and [Enter] This will add http://www. and .net to & after the word Google (works in firefox, opera etc.)
[CTRL]+[SHIFT] and [Enter] This will add http://www. and .org to & after the word Google (works in firefox, opera etc.)
For Windows XP:
Copy. CTRL+C
Cut. CTRL+X
Paste. CTRL+V
Undo. CTRL+Z
Delete. DELETE
Delete selected item permanently without placing the item in the Recycle Bin. SHIFT+DELETE
Copy selected item. CTRL while dragging an item
Create shortcut to selected item. CTRL+SHIFT while dragging an item
Rename selected item. F2
Move the insertion point to the beginning of the next word. CTRL+RIGHT ARROW
Move the insertion point to the beginning of the previous word. CTRL+LEFT ARROW
Move the insertion point to the beginning of the next paragraph. CTRL+DOWN ARROW
Move the insertion point to the beginning of the previous paragraph. CTRL+UP ARROW
Highlight a block of text. CTRL+SHIFT with any of the arrow keys
Select more than one item in a window or on the desktop, or select text within a document. SHIFT with any of the arrow keys
Select all. CTRL+A
Search for a file or folder. F3
View properties for the selected item. ALT+ENTER
Close the active item, or quit the active program. ALT+F4
Opens the shortcut menu for the active window. ALT+SPACEBAR
Close the active document in programs that allow you to have multiple documents open simultaneously. CTRL+F4
Switch between open items. ALT+TAB
Cycle through items in the order they were opened. ALT+ESC
Cycle through screen elements in a window or on the desktop. F6
Display the Address bar list in My Computer or Windows Explorer. F4
Display the shortcut menu for the selected item. SHIFT+F10
Display the System menu for the active window. ALT+SPACEBAR
Display the Start menu. CTRL+ESC
Display the corresponding menu. ALT+Underlined letter in a menu name
Carry out the corresponding command. Underlined letter in a command name on an open menu
Activate the menu bar in the active program. F10
Open the next menu to the right, or open a submenu. RIGHT ARROW
Open the next menu to the left, or close a submenu. LEFT ARROW
Refresh the active window. F5
View the folder one level up in My Computer or Windows Explorer. BACKSPACE
Cancel the current task. ESC
SHIFT when you insert a CD into the CD-ROM drive Prevent the CD from automatically playing.
Use these keyboard shortcuts for dialog boxes:
To Press
Move forward through tabs. CTRL+TAB
Move backward through tabs. CTRL+SHIFT+TAB
Move forward through options. TAB
Move backward through options. SHIFT+TAB
Carry out the corresponding command or select the corresponding option. ALT+Underlined letter
Carry out the command for the active option or button. ENTER
Select or clear the check box if the active option is a check box. SPACEBAR
Select a button if the active option is a group of option buttons. Arrow keys
Display Help. F1
Display the items in the active list. F4
Open a folder one level up if a folder is selected in the Save As or Open dialog box. BACKSPACE
If you have a Microsoft Natural Keyboard, or any other compatible keyboard that includes the Windows logo key and the Application key , you can use these keyboard shortcuts:
Display or hide the Start menu. WIN Key
Display the System Properties dialog box. WIN Key+BREAK
Show the desktop. WIN Key+D
Minimize all windows. WIN Key+M
Restores minimized windows. WIN Key+Shift+M
Open My Computer. WIN Key+E
Search for a file or folder. WIN Key+F
Search for computers. CTRL+WIN Key+F
Display Windows Help. WIN Key+F1
Lock your computer if you are connected to a network domain, or switch users if you are not connected to a network domain. WIN Key+ L
Open the Run dialog box. WIN Key+R
Open Utility Manager. WIN Key+U
accessibility keyboard shortcuts:
Switch FilterKeys on and off. Right SHIFT for eight seconds
Switch High Contrast on and off. Left ALT+left SHIFT+PRINT SCREEN
Switch MouseKeys on and off. Left ALT +left SHIFT +NUM LOCK
Switch StickyKeys on and off. SHIFT five times
Switch ToggleKeys on and off. NUM LOCK for five seconds
Open Utility Manager. WIN Key+U
shortcuts you can use with Windows Explorer:
Display the bottom of the active window. END
Display the top of the active window. HOME
Display all subfolders under the selected folder. NUM LOCK+ASTERISK on numeric keypad (*)
Display the contents of the selected folder. NUM LOCK+PLUS SIGN on numeric keypad (+)
Collapse the selected folder. NUM LOCK+MINUS SIGN on numeric keypad (-)
Collapse current selection if it's expanded, or select parent folder. LEFT ARROW
Display current selection if it's collapsed, or select first subfolder. RIGHT ARROW
I use the following keyboard shortcuts every day:
Windows key + R = Run menu
This is usually followed by:
cmd = Command Prompt
iexplore + "web address" = Internet Explorer
compmgmt.msc = Computer Management
dhcpmgmt.msc = DHCP Management
dnsmgmt.msc = DNS Management
services.msc = Services
eventvwr = Event Viewer
dsa.msc = Active Directory Users and Computers
dssite.msc = Active Directory Sites and Services
Windows key + E = Explorer
ALT + Tab = Switch between windows
ALT, Space, X = Maximize window
CTRL + Shift + Esc = Task Manager
Windows key + Break = System properties
Windows key + F = Search
Windows key + D = Hide/Display all windows
CTRL + C = copy
CTRL + X = cut
CTRL + V = paste
Also don't forget about the "Right-click" key next to the right Windows key on your keyboard. Using the arrows and that key can get just about anything done once you've opened up any program.
Keyboard Shortcuts
[Alt] and [Esc] Switch between running applications
[Alt] and letter Select menu item by underlined letter
[Ctrl] and [Esc] Open Program Menu
[Ctrl] and [F4] Close active document or group windows (does not work with some applications)
[Alt] and [F4] Quit active application or close current window
[Alt] and [-] Open Control menu for active document
Ctrl] Lft., Rt. arrow Move cursor forward or back one word
Ctrl] Up, Down arrow Move cursor forward or back one paragraph
[F1] Open Help for active application
Windows+M Minimize all open windows
Shift+Windows+M Undo minimize all open windows
Windows+F1 Open Windows Help
Windows+Tab Cycle through the Taskbar buttons
Windows+Break Open the System Properties dialog box
Accessibility Shortcuts
Right SHIFT for eight seconds........ Switch FilterKeys on and off.
Left ALT +left SHIFT +PRINT SCREEN....... Switch High Contrast on and off.
Left ALT +left SHIFT +NUM LOCK....... Switch MouseKeys on and off.
SHIFT....... five times Switch StickyKeys on and off.
NUM LOCK...... for five seconds Switch ToggleKeys on and off.
Explorer Shortcuts
END....... Display the bottom of the active window.
HOME....... Display the top of the active window.
NUM LOCK+ASTERISK....... on numeric keypad (*) Display all subfolders under the selected folder.
NUM LOCK+PLUS SIGN....... on numeric keypad (+) Display the contents of the selected folder.
NUM LOCK+MINUS SIGN....... on numeric keypad (-) Collapse the selected folder.
LEFT ARROW...... Collapse current selection if it's expanded, or select parent folder.
RIGHT ARROW....... Display current selection if it's collapsed, or select first subfolder.
Type the following commands in your Run Box (Windows Key + R) or Start Run
devmgmt.msc = Device Manager
msinfo32 = System Information
cleanmgr = Disk Cleanup
ntbackup = Backup or Restore Wizard (Windows Backup Utility)
mmc = Microsoft Management Console
excel = Microsoft Excel (If Installed)
msaccess = Microsoft Access (If Installed)
powerpnt = Microsoft PowerPoint (If Installed)
winword = Microsoft Word (If Installed)
frontpg = Microsoft FrontPage (If Installed)
notepad = Notepad
wordpad = WordPad
calc = Calculator
msmsgs = Windows Messenger
mspaint = Microsoft Paint
wmplayer = Windows Media Player
rstrui = System Restore
netscp6 = Netscape 6.x
netscp = Netscape 7.x
netscape = Netscape 4.x
waol = America Online
control = Opens the Control Panel
control printers = Opens the Printers Dialog
Internet Browser
Type in Your address "google", then press
[CTRL] and [Enter] This will add http://www. and .com to & after the word Google
[SHIFT] and [Enter] This will add http://www. and .net to & after the word Google (works in firefox, opera etc.)
[CTRL]+[SHIFT] and [Enter] This will add http://www. and .org to & after the word Google (works in firefox, opera etc.)
For Windows XP:
Copy. CTRL+C
Cut. CTRL+X
Paste. CTRL+V
Undo. CTRL+Z
Delete. DELETE
Delete selected item permanently without placing the item in the Recycle Bin. SHIFT+DELETE
Copy selected item. CTRL while dragging an item
Create shortcut to selected item. CTRL+SHIFT while dragging an item
Rename selected item. F2
Move the insertion point to the beginning of the next word. CTRL+RIGHT ARROW
Move the insertion point to the beginning of the previous word. CTRL+LEFT ARROW
Move the insertion point to the beginning of the next paragraph. CTRL+DOWN ARROW
Move the insertion point to the beginning of the previous paragraph. CTRL+UP ARROW
Highlight a block of text. CTRL+SHIFT with any of the arrow keys
Select more than one item in a window or on the desktop, or select text within a document. SHIFT with any of the arrow keys
Select all. CTRL+A
Search for a file or folder. F3
View properties for the selected item. ALT+ENTER
Close the active item, or quit the active program. ALT+F4
Opens the shortcut menu for the active window. ALT+SPACEBAR
Close the active document in programs that allow you to have multiple documents open simultaneously. CTRL+F4
Switch between open items. ALT+TAB
Cycle through items in the order they were opened. ALT+ESC
Cycle through screen elements in a window or on the desktop. F6
Display the Address bar list in My Computer or Windows Explorer. F4
Display the shortcut menu for the selected item. SHIFT+F10
Display the System menu for the active window. ALT+SPACEBAR
Display the Start menu. CTRL+ESC
Display the corresponding menu. ALT+Underlined letter in a menu name
Carry out the corresponding command. Underlined letter in a command name on an open menu
Activate the menu bar in the active program. F10
Open the next menu to the right, or open a submenu. RIGHT ARROW
Open the next menu to the left, or close a submenu. LEFT ARROW
Refresh the active window. F5
View the folder one level up in My Computer or Windows Explorer. BACKSPACE
Cancel the current task. ESC
SHIFT when you insert a CD into the CD-ROM drive Prevent the CD from automatically playing.
Use these keyboard shortcuts for dialog boxes:
To Press
Move forward through tabs. CTRL+TAB
Move backward through tabs. CTRL+SHIFT+TAB
Move forward through options. TAB
Move backward through options. SHIFT+TAB
Carry out the corresponding command or select the corresponding option. ALT+Underlined letter
Carry out the command for the active option or button. ENTER
Select or clear the check box if the active option is a check box. SPACEBAR
Select a button if the active option is a group of option buttons. Arrow keys
Display Help. F1
Display the items in the active list. F4
Open a folder one level up if a folder is selected in the Save As or Open dialog box. BACKSPACE
If you have a Microsoft Natural Keyboard, or any other compatible keyboard that includes the Windows logo key and the Application key , you can use these keyboard shortcuts:
Display or hide the Start menu. WIN Key
Display the System Properties dialog box. WIN Key+BREAK
Show the desktop. WIN Key+D
Minimize all windows. WIN Key+M
Restores minimized windows. WIN Key+Shift+M
Open My Computer. WIN Key+E
Search for a file or folder. WIN Key+F
Search for computers. CTRL+WIN Key+F
Display Windows Help. WIN Key+F1
Lock your computer if you are connected to a network domain, or switch users if you are not connected to a network domain. WIN Key+ L
Open the Run dialog box. WIN Key+R
Open Utility Manager. WIN Key+U
accessibility keyboard shortcuts:
Switch FilterKeys on and off. Right SHIFT for eight seconds
Switch High Contrast on and off. Left ALT+left SHIFT+PRINT SCREEN
Switch MouseKeys on and off. Left ALT +left SHIFT +NUM LOCK
Switch StickyKeys on and off. SHIFT five times
Switch ToggleKeys on and off. NUM LOCK for five seconds
Open Utility Manager. WIN Key+U
shortcuts you can use with Windows Explorer:
Display the bottom of the active window. END
Display the top of the active window. HOME
Display all subfolders under the selected folder. NUM LOCK+ASTERISK on numeric keypad (*)
Display the contents of the selected folder. NUM LOCK+PLUS SIGN on numeric keypad (+)
Collapse the selected folder. NUM LOCK+MINUS SIGN on numeric keypad (-)
Collapse current selection if it's expanded, or select parent folder. LEFT ARROW
Display current selection if it's collapsed, or select first subfolder. RIGHT ARROW
Feb 14, 2008
Guide to avoiding virus infections with wide eyes open
Computer viruses are everywhere! This guide will show you how to stay alert and how to avoid getting infections on your computer. Having an updated virus scanner is only a small part of this, there are many ways that you can prevent having viruses other than a virus scanner, as it will not always save you.
Types of viruses
There are many type of viruses. Typical viruses are simply programs or scripts that will do various damage to your computer, such as corrupting files, copying itself into files, slowly deleting all your hard drive etc. This depends on the virus. Most viruses also mail themselves to other people in the address book. This way they spread really fast and appear at others' inboxes as too many people still fall for these. Most viruses will try to convince you to open the attachment, but I have never got one that tricked me. In fact, I found myself emailing people just to make sure they really did send me something. It does not hurt to be safe.
Worms
Worms are different type of viruses, but the same idea, but they are usually designed to copy themselves a lot over a network and usually try to eat up as much bandwidth as possible by sending commands to servers to try to get in. The code red worm is a good example of this. This worm breaks in a security hole in Microsoft IIS (Internet Information Server) in which is a badly coded http server that, despite the security risks, a lot of people use it. When the worm successfully gets in, it will try to go into other servers from there. When IceTeks was run on a dedicated server at my house, there was about 10 or so attempts per day, but because we ran Apache, the attempts did not do anything but waste bandwidth and not much as I had it fixed a special way. Some worms such as the SQL slammer will simply send themselves over and over so many times that they will clog up networks, and sometimes all of the internet. Worms usually affect servers more than home users, but again, this depends on what worm it is. It is suspected that most worms are efforts from the RIAA to try to stop piracy, so they try to clog up networks that could contain files. Unfortunately, the RIAA have the authority to do these damages and even if caught, nothing can be done.
Trojans
Trojans are another type of virus. They are simply like a server in which enables hackers to get into and control the computer. A trojan such as Subseven can enable a hacker to do various things such as control the mouse, eject the cd-rom drive, delete/download/upload files and much more.
MBR virues
Boot sector viruses are another type, they are similar to file viruses, but instead they go in the boot sector and can cause serious damage when the computer is booted, some can easily format your drive simply by booting your computer. These are hard to remove.
Most viruses have various characteristics. For example, a worm can also be a trojan and also infect the boot sector. It all depends on how the virus is written and what it is designed to do. That's why there are not really strong structured categories, as they can easily mix one in the other.
Know the potentially dangerous files
Like any other files, viruses must be opened in order to do something. Most viruses come through e-mail as an attachment. Some will make it look like it's someone you know, and it will try to convince you to open an attachment. Never open attachments at any cost! Some viruses will infect files in programs, so opening a program will actually open the virus, maybe the same one, or another part of it.
All files have what is called an extension; This is the 3 last letters after the last period. For example, setup.exe has a file extension of .exe.
Extensions to watch out for are .exe .com .bat .scr .pif .vbs and others, but these are the most seen. .exe .com .bat .pif and .scr are valid extensions for executables. A virus writer will simply rename it to one of these and it will work the same way. .pif is a shortcut to an ms-dos program and will have the ms dos icon, but will still execute whatever code is in it, so an .exe can be renamed to .pif and be run the same way. .bat is a batch file, which can contain instructions to do various file activities, but again, a .exe can be renamed to .bat and it will execute it! .vbs is a visual basic script. For some reason, Microsoft provides this scripting language along with the scripting host to make it more convenient to design and write viruses quickly and easily, I've never seen another use for this scripting language other than for writing viruses. There are programs that are written with that language, but it is compiled into an exe. Exe is the usual extension for programs, you would not have a software CD install a bunch of vbs files all over!
Bottom line is, if you don't know what a file is just don't open it. Some viruses will sometimes be named a way as to mask the real file extension to make it look like a harmless file such as a image file. This is easily noticed, but can still be missed. Simply don't open unexpected files.
If you get something that appears like something legit, just ask the person it came from if they sent it. Most viruses use a friend's address to make it look like it comes from them. The virus does this by using the person's address when sending itself to the address book contacts.
Downloads
Email is not the only way to get viruses; P2P (file sharing programs such as kazaa, winmx, direct connect etc) is also another way to get viruses.
When downloading programs, the main thing to watch out for is the file size. If you are downloading a program that you expect to be rather large such as a game, don't grab a file that is 10KB, since it's most likely a virus. However, I've been caught with a virus even with large files, so file size is not the only thing to watch, as an exe is still valid even if junk is added at the end, so a 64KB virus will still function even if it is turned into 650MB.
Icons are something to look for too, fortunately, virus writers don't take time to put icons. If your download should be a setup file, you should see the icon of a setup file. If it's just the blank icon that typical plain or corrupted exes have, don't open it.
Another thing to do, which should be obvious, is to scan the file for viruses using updated virus definitions. But don't rely on only your virus scanner, as they are not perfect, and if the virus has not been reported to them yet, they won't know to create a definition for it!
Changing settings to stay safe
If you do open a virus, you want to avoid it going to all your friends. The simplest thing to do is to NOT use the windows address book. It is easy for viruses to get through and Microsoft is not doing anything about it. Just don't use it. Put them in spreadsheet or even better write them down somewhere. Don't use the address book.
Another "feature" to avoid is the auto preview. Some viruses can attempt to open themselves just by opening the email. There are security holes in Microsoft mail programs that allow this. In Microsoft Outlook, click on the view menu and remove auto preview. You need to do this for every folder, but the inbox is most important. In Outlook Express, click on the view menu and go to layout. In the dialog box, you will see a check box for show preview pane. Uncheck it and click ok.
Another thing you should change, especially if you download a lot, is the option that allows you to view the file extension. In Win98, go in any folder, click on view then folder options and choose the view tab and where it says hide file extension for known types, uncheck it. In win2k, it is the same process, but instead, go in the control panel and open the folder options icon.
Avoiding server worms
Some viruses, mostly worms, can exploit through servers and affect other servers from servers that have been infected. A good example is the SQL slammer. This was a worm that affected SQL servers run by Microsoft IIS and Microsoft SQL Server. Once the worm gets in, that particular server starts trying to find more exploitable driving internet connections to a halt in the process. Servers running Apache were unaffected by that, except for the many hits to try to get in. IceTeks received about 100 hits per day when it was run on a dedicated home server. Most hits came from major ISPs and other big websites that had no clue they were still affected.
The simple solution to avoid these types of viruses is to NOT use Microsoft based server software for your server, especially if it is a public server. The operating system is also crucial, but the actual server software is much more. Apache, which is free, is much more secure than Microsoft based server programs such as IIS. IIS may be easier to understand and administer, but it saves a lot of hassle to learn how to use Apache. IIS has a large number of vulnerabilities, such as the ability to gain access to cmd.exe and basically delete the whole drive by doing a ../ request in the address bar. These don't require viruses, but simply commands, but there are worms written to automatically make these commands. The code red does this.
Removing a virus
The best way to do this is to do a clean install. However, depending on how bad the virus is, a simple clean install won't remove it. So to be extra sure, you'll want to do a low level format. This is especially true of you got a boot sector virus, as even repartitioning and formatting won't quite remove it, but sometimes you can get away with an fdisk /mbr, but not all the time. here are various removal tools for viruses, it is good to use them and see if they work, but proceeding with the clean install is recommended. You never know if the virus is completely removed by deleting files you suspect are infected. Some viruses such as the Bugbear will close anti virus programs and other programs to make it hard and annoying to figure out what to do. A clean install is the best way to ensure that it's gone for good.
Viruses are out there, don't be one of the many infected ones! Stay alert and stay safe! Don't open unexpected files, regularly update your virus definitions and scan downloaded files!
I hope this article was useful for you!
Types of viruses
There are many type of viruses. Typical viruses are simply programs or scripts that will do various damage to your computer, such as corrupting files, copying itself into files, slowly deleting all your hard drive etc. This depends on the virus. Most viruses also mail themselves to other people in the address book. This way they spread really fast and appear at others' inboxes as too many people still fall for these. Most viruses will try to convince you to open the attachment, but I have never got one that tricked me. In fact, I found myself emailing people just to make sure they really did send me something. It does not hurt to be safe.
Worms
Worms are different type of viruses, but the same idea, but they are usually designed to copy themselves a lot over a network and usually try to eat up as much bandwidth as possible by sending commands to servers to try to get in. The code red worm is a good example of this. This worm breaks in a security hole in Microsoft IIS (Internet Information Server) in which is a badly coded http server that, despite the security risks, a lot of people use it. When the worm successfully gets in, it will try to go into other servers from there. When IceTeks was run on a dedicated server at my house, there was about 10 or so attempts per day, but because we ran Apache, the attempts did not do anything but waste bandwidth and not much as I had it fixed a special way. Some worms such as the SQL slammer will simply send themselves over and over so many times that they will clog up networks, and sometimes all of the internet. Worms usually affect servers more than home users, but again, this depends on what worm it is. It is suspected that most worms are efforts from the RIAA to try to stop piracy, so they try to clog up networks that could contain files. Unfortunately, the RIAA have the authority to do these damages and even if caught, nothing can be done.
Trojans
Trojans are another type of virus. They are simply like a server in which enables hackers to get into and control the computer. A trojan such as Subseven can enable a hacker to do various things such as control the mouse, eject the cd-rom drive, delete/download/upload files and much more.
MBR virues
Boot sector viruses are another type, they are similar to file viruses, but instead they go in the boot sector and can cause serious damage when the computer is booted, some can easily format your drive simply by booting your computer. These are hard to remove.
Most viruses have various characteristics. For example, a worm can also be a trojan and also infect the boot sector. It all depends on how the virus is written and what it is designed to do. That's why there are not really strong structured categories, as they can easily mix one in the other.
Know the potentially dangerous files
Like any other files, viruses must be opened in order to do something. Most viruses come through e-mail as an attachment. Some will make it look like it's someone you know, and it will try to convince you to open an attachment. Never open attachments at any cost! Some viruses will infect files in programs, so opening a program will actually open the virus, maybe the same one, or another part of it.
All files have what is called an extension; This is the 3 last letters after the last period. For example, setup.exe has a file extension of .exe.
Extensions to watch out for are .exe .com .bat .scr .pif .vbs and others, but these are the most seen. .exe .com .bat .pif and .scr are valid extensions for executables. A virus writer will simply rename it to one of these and it will work the same way. .pif is a shortcut to an ms-dos program and will have the ms dos icon, but will still execute whatever code is in it, so an .exe can be renamed to .pif and be run the same way. .bat is a batch file, which can contain instructions to do various file activities, but again, a .exe can be renamed to .bat and it will execute it! .vbs is a visual basic script. For some reason, Microsoft provides this scripting language along with the scripting host to make it more convenient to design and write viruses quickly and easily, I've never seen another use for this scripting language other than for writing viruses. There are programs that are written with that language, but it is compiled into an exe. Exe is the usual extension for programs, you would not have a software CD install a bunch of vbs files all over!
Bottom line is, if you don't know what a file is just don't open it. Some viruses will sometimes be named a way as to mask the real file extension to make it look like a harmless file such as a image file. This is easily noticed, but can still be missed. Simply don't open unexpected files.
If you get something that appears like something legit, just ask the person it came from if they sent it. Most viruses use a friend's address to make it look like it comes from them. The virus does this by using the person's address when sending itself to the address book contacts.
Downloads
Email is not the only way to get viruses; P2P (file sharing programs such as kazaa, winmx, direct connect etc) is also another way to get viruses.
When downloading programs, the main thing to watch out for is the file size. If you are downloading a program that you expect to be rather large such as a game, don't grab a file that is 10KB, since it's most likely a virus. However, I've been caught with a virus even with large files, so file size is not the only thing to watch, as an exe is still valid even if junk is added at the end, so a 64KB virus will still function even if it is turned into 650MB.
Icons are something to look for too, fortunately, virus writers don't take time to put icons. If your download should be a setup file, you should see the icon of a setup file. If it's just the blank icon that typical plain or corrupted exes have, don't open it.
Another thing to do, which should be obvious, is to scan the file for viruses using updated virus definitions. But don't rely on only your virus scanner, as they are not perfect, and if the virus has not been reported to them yet, they won't know to create a definition for it!
Changing settings to stay safe
If you do open a virus, you want to avoid it going to all your friends. The simplest thing to do is to NOT use the windows address book. It is easy for viruses to get through and Microsoft is not doing anything about it. Just don't use it. Put them in spreadsheet or even better write them down somewhere. Don't use the address book.
Another "feature" to avoid is the auto preview. Some viruses can attempt to open themselves just by opening the email. There are security holes in Microsoft mail programs that allow this. In Microsoft Outlook, click on the view menu and remove auto preview. You need to do this for every folder, but the inbox is most important. In Outlook Express, click on the view menu and go to layout. In the dialog box, you will see a check box for show preview pane. Uncheck it and click ok.
Another thing you should change, especially if you download a lot, is the option that allows you to view the file extension. In Win98, go in any folder, click on view then folder options and choose the view tab and where it says hide file extension for known types, uncheck it. In win2k, it is the same process, but instead, go in the control panel and open the folder options icon.
Avoiding server worms
Some viruses, mostly worms, can exploit through servers and affect other servers from servers that have been infected. A good example is the SQL slammer. This was a worm that affected SQL servers run by Microsoft IIS and Microsoft SQL Server. Once the worm gets in, that particular server starts trying to find more exploitable driving internet connections to a halt in the process. Servers running Apache were unaffected by that, except for the many hits to try to get in. IceTeks received about 100 hits per day when it was run on a dedicated home server. Most hits came from major ISPs and other big websites that had no clue they were still affected.
The simple solution to avoid these types of viruses is to NOT use Microsoft based server software for your server, especially if it is a public server. The operating system is also crucial, but the actual server software is much more. Apache, which is free, is much more secure than Microsoft based server programs such as IIS. IIS may be easier to understand and administer, but it saves a lot of hassle to learn how to use Apache. IIS has a large number of vulnerabilities, such as the ability to gain access to cmd.exe and basically delete the whole drive by doing a ../ request in the address bar. These don't require viruses, but simply commands, but there are worms written to automatically make these commands. The code red does this.
Removing a virus
The best way to do this is to do a clean install. However, depending on how bad the virus is, a simple clean install won't remove it. So to be extra sure, you'll want to do a low level format. This is especially true of you got a boot sector virus, as even repartitioning and formatting won't quite remove it, but sometimes you can get away with an fdisk /mbr, but not all the time. here are various removal tools for viruses, it is good to use them and see if they work, but proceeding with the clean install is recommended. You never know if the virus is completely removed by deleting files you suspect are infected. Some viruses such as the Bugbear will close anti virus programs and other programs to make it hard and annoying to figure out what to do. A clean install is the best way to ensure that it's gone for good.
Viruses are out there, don't be one of the many infected ones! Stay alert and stay safe! Don't open unexpected files, regularly update your virus definitions and scan downloaded files!
I hope this article was useful for you!
Jan 21, 2008
OverBurning - Data Capacity of CDs
Abstract
You can fit on a S/VCD without overburning:
- approx. 735 MB of MPEG data onto a 74min/650MB disc
- approx. 795 MB of MPEG data onto an 80min/700MB disc
You can fit on a CD-ROM without overburning:
- approx. 650 MB of data onto a 74min/650MB disc
- approx. 703 MB of data onto an 80min/700MB disc
----------------------------------------------------------------
Introduction
Let us ignore for now the terms of megabyte for CD capacity and try to understand how the data is stored on a CD.
As well all know, the data is stored digitally as binary data. This means, however the actual information is actually kept on the disc, this information is in the form of "1"s and "0"s. Physically, the information on a CD is as pits on a thin sheet of metal (aluminium).
An a CD-R disc, the data is physically on an organic dye layer which simulates the metal layer on a real pressed CD.
----------------------------------------------------------------
How is the information structured
Now, on the CD, the information isn't just organised from beginning to end willy-nilly. Otherwise, it would be really hard to find a useful piece of information on the CD.
Rather, the information is organised in sectors. Consider a sector as like a page in a book. Just like you are able to quickly find something in a book if you know the page number, you can quickly find something on a CD if you know the sector number.
Now, remember that the CD was original made to hold audio data. It was decided, that the CD would would 75 sectors per second of audio. Although I cannot guess where this number comes from, it is quite appropriate for the audio CD. It means that you can "seek" an audio CD accurately to 1/75th of a second -- which is more than enough for consumer purposes.
Now, with this in mind, we can work out the total data capacity of user data for 1 sector.
----------------------------------------------------------------
The total data capacity of user data of 1 sector on a CD
CD audio uses uncompressed PCM stereo audio, 16-bit resolution sampled at 44.1 kHz.
Thus 1 second of audio contains:
16 bits/channel * 2 channels * 44100 samples/second * 1 second
= 1411200 bits
= 176400 bytes
Since there are 75 sectors per second
1 sector
= 176400 bytes / 75
= 2352 bytes
One sector on a CD contains 2352 bytes max.
----------------------------------------------------------------
The concept of different MODES and FORMS of burning
Now, audio CD was well and good, but the medium would become much more useful if you could store other data on the disc as well. This became to be know as CD-ROM of course.
Now, the audio-CD uses the ENTIRE sector for audio data.
However, for CD-ROMs this caused a problem. Simply, CDs and the CD reading mechanisms were not 100% faultless. That is, errors (indeed frequent errors) could be made during the reading. For audio CDs, this does not matter as much as you could simply interpolate from the adjacent audio samples. This will obviously NOT DO for data CDs. A single bit error could lead to a program being unexecutable or ruin an achive file.
Thus, for CD-ROMs, part of each sector is devoted to error correction codes and error detection codes. The CD-R FAQ has the details, but in effect, only 2048 bytes out of a total of 2352 bytes in each sector is available for user data on a data CD.
This burning mode is either MODE1 or MODE2 Form1.
----------------------------------------------------------------
MODE2 Form2 sectors of VCDs and SVCDs
Now, for VCDs and SVCDs, the video tracks do not necessarily require the robust error correction as normal data on a CD-ROM. However, there is still some overhead per sector that is used for something other than video data (e.g., sync headers).
S/VCDs video tracks are burnt in what is called MODE2 Form2 sectors. In this mode, only 2324 bytes out of a total of 2352 bytes in each sector is available for user data.
This is MUCH MORE than for CD-ROMs, but still less per sector than audio CD.
----------------------------------------------------------------
The disc capacities of CD-ROMs, audio-CDs and VCDs
Now, obviously what ultimately determines the capacity of a disc is the total number of sectors it contains. This is similar to the total number of pages in a blank exercise book (if you recall the book analogy).
The secondary determinant is the burning mode of the disc.
For audio CDs, it is as if you could fill each page from top to bottom with audio data as the entire sector is used for audio data.
For CD-ROMs, it is as if you need to first rule a margin and then leave the bottom part of each page for footnotes (headers + ECC + EDC). The amount of text you can actually write per page is then less due to these other constraints.
For S/VCDs, we still need to rule a margin on the page, but we don't have to worry about the footnotes (headers). We can fit MORE text than a CD-ROM, but less than an audio-CD.
Now remember, 1 second on a CD = 75 sectors.
Thus:
- 74 min CD = 333,000 sectors
- 80 min CD = 360,000 sectors
Data capacity in Mb for an audio-CD
74 min
= 333,000 sectors * 2352 bytes / sector
= 783216000 bytes
= 746.9 Mb
80 min
= 360,000 sectors * 2352 bytes / sector
= 846720000 bytes
= 807.5 Mb
Data capacity in Mb for a CD-ROM
74 min
= 333,000 sectors * 2048 bytes / sector
= 681984000 bytes
= 650.4 Mb
80 min
= 360,000 sectors * 2048 bytes / sector
= 737280000 bytes
= 703.1 Mb
Data capacity in Mb for a S/VCD
74 min
= 333,000 sectors * 2324 bytes / sector
= 773892000 bytes
= 738.0 Mb
80 min
= 360,000 sectors * 2324 bytes / sector
= 836640000 bytes
= 797.9 Mb
----------------------------------------------------------------
Conclusions
As you can see, the often quoted capacities of 650MB and 700MB refer to CD-ROM capacities.
Due to the fact that S/VCDs use a different burning mode where MORE of each sector is available as user data, the relatively capacities are HIGHER.
Now, since S/VCDs are not composed of PURELY video tracks and have some unavoidable overheads, the actually total capacity left for video tracks is a few Mb less for each disc (about 735 Mb for 74min discs and 795 Mb for 80min discs). This is where the often quoted capacities of 740MB and 800MB come from. They are quite accurate.
All these capacities are available BEFORE overburning. Overburning is where you burn MORE sectors than the disc is rated for. If you overburn, you can typically achieve about 1-2 minutes of additional capacity (depending on your drive and media).
You can fit on a S/VCD without overburning:
- approx. 735 MB of MPEG data onto a 74min/650MB disc
- approx. 795 MB of MPEG data onto an 80min/700MB disc
You can fit on a CD-ROM without overburning:
- approx. 650 MB of data onto a 74min/650MB disc
- approx. 703 MB of data onto an 80min/700MB disc
----------------------------------------------------------------
Introduction
Let us ignore for now the terms of megabyte for CD capacity and try to understand how the data is stored on a CD.
As well all know, the data is stored digitally as binary data. This means, however the actual information is actually kept on the disc, this information is in the form of "1"s and "0"s. Physically, the information on a CD is as pits on a thin sheet of metal (aluminium).
An a CD-R disc, the data is physically on an organic dye layer which simulates the metal layer on a real pressed CD.
----------------------------------------------------------------
How is the information structured
Now, on the CD, the information isn't just organised from beginning to end willy-nilly. Otherwise, it would be really hard to find a useful piece of information on the CD.
Rather, the information is organised in sectors. Consider a sector as like a page in a book. Just like you are able to quickly find something in a book if you know the page number, you can quickly find something on a CD if you know the sector number.
Now, remember that the CD was original made to hold audio data. It was decided, that the CD would would 75 sectors per second of audio. Although I cannot guess where this number comes from, it is quite appropriate for the audio CD. It means that you can "seek" an audio CD accurately to 1/75th of a second -- which is more than enough for consumer purposes.
Now, with this in mind, we can work out the total data capacity of user data for 1 sector.
----------------------------------------------------------------
The total data capacity of user data of 1 sector on a CD
CD audio uses uncompressed PCM stereo audio, 16-bit resolution sampled at 44.1 kHz.
Thus 1 second of audio contains:
16 bits/channel * 2 channels * 44100 samples/second * 1 second
= 1411200 bits
= 176400 bytes
Since there are 75 sectors per second
1 sector
= 176400 bytes / 75
= 2352 bytes
One sector on a CD contains 2352 bytes max.
----------------------------------------------------------------
The concept of different MODES and FORMS of burning
Now, audio CD was well and good, but the medium would become much more useful if you could store other data on the disc as well. This became to be know as CD-ROM of course.
Now, the audio-CD uses the ENTIRE sector for audio data.
However, for CD-ROMs this caused a problem. Simply, CDs and the CD reading mechanisms were not 100% faultless. That is, errors (indeed frequent errors) could be made during the reading. For audio CDs, this does not matter as much as you could simply interpolate from the adjacent audio samples. This will obviously NOT DO for data CDs. A single bit error could lead to a program being unexecutable or ruin an achive file.
Thus, for CD-ROMs, part of each sector is devoted to error correction codes and error detection codes. The CD-R FAQ has the details, but in effect, only 2048 bytes out of a total of 2352 bytes in each sector is available for user data on a data CD.
This burning mode is either MODE1 or MODE2 Form1.
----------------------------------------------------------------
MODE2 Form2 sectors of VCDs and SVCDs
Now, for VCDs and SVCDs, the video tracks do not necessarily require the robust error correction as normal data on a CD-ROM. However, there is still some overhead per sector that is used for something other than video data (e.g., sync headers).
S/VCDs video tracks are burnt in what is called MODE2 Form2 sectors. In this mode, only 2324 bytes out of a total of 2352 bytes in each sector is available for user data.
This is MUCH MORE than for CD-ROMs, but still less per sector than audio CD.
----------------------------------------------------------------
The disc capacities of CD-ROMs, audio-CDs and VCDs
Now, obviously what ultimately determines the capacity of a disc is the total number of sectors it contains. This is similar to the total number of pages in a blank exercise book (if you recall the book analogy).
The secondary determinant is the burning mode of the disc.
For audio CDs, it is as if you could fill each page from top to bottom with audio data as the entire sector is used for audio data.
For CD-ROMs, it is as if you need to first rule a margin and then leave the bottom part of each page for footnotes (headers + ECC + EDC). The amount of text you can actually write per page is then less due to these other constraints.
For S/VCDs, we still need to rule a margin on the page, but we don't have to worry about the footnotes (headers). We can fit MORE text than a CD-ROM, but less than an audio-CD.
Now remember, 1 second on a CD = 75 sectors.
Thus:
- 74 min CD = 333,000 sectors
- 80 min CD = 360,000 sectors
Data capacity in Mb for an audio-CD
74 min
= 333,000 sectors * 2352 bytes / sector
= 783216000 bytes
= 746.9 Mb
80 min
= 360,000 sectors * 2352 bytes / sector
= 846720000 bytes
= 807.5 Mb
Data capacity in Mb for a CD-ROM
74 min
= 333,000 sectors * 2048 bytes / sector
= 681984000 bytes
= 650.4 Mb
80 min
= 360,000 sectors * 2048 bytes / sector
= 737280000 bytes
= 703.1 Mb
Data capacity in Mb for a S/VCD
74 min
= 333,000 sectors * 2324 bytes / sector
= 773892000 bytes
= 738.0 Mb
80 min
= 360,000 sectors * 2324 bytes / sector
= 836640000 bytes
= 797.9 Mb
----------------------------------------------------------------
Conclusions
As you can see, the often quoted capacities of 650MB and 700MB refer to CD-ROM capacities.
Due to the fact that S/VCDs use a different burning mode where MORE of each sector is available as user data, the relatively capacities are HIGHER.
Now, since S/VCDs are not composed of PURELY video tracks and have some unavoidable overheads, the actually total capacity left for video tracks is a few Mb less for each disc (about 735 Mb for 74min discs and 795 Mb for 80min discs). This is where the often quoted capacities of 740MB and 800MB come from. They are quite accurate.
All these capacities are available BEFORE overburning. Overburning is where you burn MORE sectors than the disc is rated for. If you overburn, you can typically achieve about 1-2 minutes of additional capacity (depending on your drive and media).
Jan 10, 2008
Converting to NTFS
Your hard drive must be formatted with a file system such as FAT, FAT32 or NTFS so that Windows can be installed on to it. This system determines how files are named, organised and stored on the drive. If you’re not using it already, NTFS (New Technology File System) is recommended for Windows XP because of the additional functionality it offers. If your PC came with Windows XP pre-installed then there’s a chance that you’re already using NTFS. If you’ve upgraded from Windows 98 or Windows Me you may still be using FAT or FAT 32. The option to change over to NTFS would have been available during the upgrade process. Don’t worry if you skipped this as it’s possible to convert at any time from within Windows XP without losing any data.
The recommended option
There are a number of features in Windows XP that will only work if the NTFS file system is present, which is why it’s suggested you make use of it. File and folder permissions, encryption and privacy options are just some of those you’ll be able to access. In particular, those of you who have set up user accounts will find NTFS invaluable. For instance, if you continue to use FAT or FAT32 anyone with physical access to the drive will be able to access the files and folders that are stored there. However, with NTFS you’ll be able to use a level of encryption (Professional Edition only) that will enable you to protect your data.
You’ll also find NTFS more reliable in that it’s more able to recover from disk errors than its FAT or FAT32 counterparts. A log of all disk activity is kept so should a crash occur, Windows XP can use this information to repair the file system when your PC boots up again. To find out what file system you’re using, open My Computer, right-click your main hard drive and choose Properties. Take a look at the General tab to see confirmation of the file system that’s in use.
Convert now
You can use the convert tool in Windows XP to change the file system on your hard disk from FAT or FAT32 to NTFS. The whole process is safe and your existing data won’t be destroyed. To begin, click Start -> Run, type cmd and press [Return]. At the command prompt type convert c: /fs:ntfs and press [Return] (where ‘c’ is the letter of the drive you’re converting). When you try and run the convert utility, it’s likely that Windows XP will be using your paging file so the process won’t be completed immediately. Therefore, you’ll see a brief message on screen informing you that the conversion will take place instead the next time Windows starts up. Having restarted, the Check Disk utility will run, the conversion will be performed automatically and you may find that your PC will reboot twice more.
The benefits
With your drive now running NTFS, it’s time to take advantage of the new options that are available. Having created a number of different user accounts you can now control the level of access that’s granted to individual users. For example, there are going to be certain files and folders that you’ll want some users to be able to access but not others. If you have Windows XP Professional Edition you can do this immediately.
Right-click any file or folder, choose Properties and select the Security tab. A dialog will be displayed showing the names of all your users. Alongside will be two columns which enable you to select levels of access for each of them, the permissions include Full Control, Modify, Read and Write. You can then check the appropriate box to determine whether or not to Allow or Deny a particular permission. For Windows XP Home Edition users, the Security tab won’t be immediately available. To access this option you’ll need to restart your PC, pressing [F8] until a menu appears. Next select Safe Mode and wait for Windows XP to start up. You can then set your options in the same way.
Another feature is NTFS compression. It’s quick and seamless as your file or folder is decompressed automatically when you access it. (Don’t confuse this with a Zip compression utility where the files need to be extracted before they can be accessed.) Although you may have used NTFS compression on a file or folder, there’s no way of telling just by looking at it. To remedy this, open My Computer, click Tools -> Folder Options and select the View tab. Under Advanced settings, scroll down and check the option ‘Show encrypted or compressed NTFS files in color’, then click Apply and OK. Take a look at your compressed items in My Computer and you’ll see the text label has changed from black to blue. Something else that’s exclusive to Professional Edition users is the Encrypting File System (EFS). You can use this to protect your important data so that no one else can read it. Your encrypted files and folders will only be accessible when you have logged into your user account successfully.
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