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.

Feb 22, 2008

Partitioning Your Harddisk With Fdisk

Partitioning involves creating logical units on your hard drive that are then addressed as different drive letters. Not only does it help to organize your data (program files on one drive, games on another, documents on another) but also to speed up your PC. This is so because the drive head has to move a lesser distance for accessing data within one partition. You can also have different filesystems and OSs on the same hard drive.

Partitioning can be done using ‘fdisk’ in DOS/Windows 9x or ‘disk management’ in Windows 2000/ NT/XP. We will describe the procedure for fdisk, since disk management is GUI driven and the basics otherwise remain the same. While several other commercial packages like Partition Magic are available, these utilities (fdisk, computer management) are bundled with their respective OSs. You need a bootable floppy with fdisk.exe, format.com, and sys. com utilities. Before starting, decide how many partitions you want to create and their sizes. You can create one primary and one extended partition using the DOS fdisk. The extended partition can then have multiple logical partitions. Boot your machine using the bootable disk, and do the following.

Run fdisk. The utility will show you a numbered menu from where you can create, view, or delete partitions
The utility first asks you whether you want to enable large disk support. Type Y (for yes) and press enter if your hard-drive capacity is more than 4 GB. Large disk support creates a FAT32 partition, which can be greater than 2 GB.

Select the first option from fdisk menu to create a primary partition. Specify the partition size in megabytes or percentage size when prompted for it

Similarly, create an extended partition. Extended partitions by themselves do not appear as drive letters. Instead, logical partitions must be created in them, which are then assigned drive letters

Exit fdisk and reboot the computer

Fdisk automatically assigns drive letters to all the partitions. You’ll need to format each partition in order to use it. Use format.com for the same

Your hard drive is now ready for taking an OS.

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.

How To Access Your Folders From Your Taskbar

This is an easy way to get to the folders on your system without having to open a Windows Explorer Window every time you want to access files. I find it very useful to have this feature as it allows me to access my Folders and Drives immediately and saves me a lot of time.

This works in Windows XP:

1. Right Click an empty spot on your Taskbar (Between your Start Button and your System Tray).
2. Click Toolbars.
3. Click New Toolbar.
4. A Small Window will Open that allows you to pick the folder you wish to make a Toolbar. If you want to access your Desktop Without having to minimize all your windows. Just Pick Desktop. If you want to access ONLY your My Documents Folder, Select that. Any folder will work for this.
5. Click OK.
The New Tool bar will appear at the bottom of your screen next to your System Tray.

If you find this to be not useful, Repeat Steps 1 and 2 and then check click the Toolbar you created that has a check mark next to it. And it will disappear.

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.

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

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!

Feb 5, 2008

Virtual Memory Information

Tutorial Objective

This tutorial talks about anything about the virtual memory and how much virtual memory you need for your system.

Tutorial Introduction & Background

Today application is getting bigger and bigger. Therefore, it requires a bigger system memory in order for the system to hold the application data, instruction, and thread and to load it. The system needs to copy the application data from the HDD into the system memory in order for it to process and execute the data. Once the memory gets filled up with data, the system will stop loading the program. In this case, users need to add more memory onto their system to support that intense application. However, adding more system memory costs the money and the normal user only needs to run the the intense application that requires the memory only for one or two days. Therefore, virtual memory is introduced to solve that type of problem.

Terminology & Explanation

There are two types of memory, which are as follows:

* System Memory is a memory that is used to store the application data and instruction in order for the system to process and execute that application data and instruction. When you install the memory sticks to increase the system RAM, you are adding more system memory. System Memory can be known as either the physical memory or the main memory.

* Virtual Memory is a memory that uses a portion of HDD space as the memory to store the application data and instruction that the system deemed it doesn't need to process for now. Virtual Memory can be known as the logical memory, and it controls by the Operating System, which is Microsoft Windows. Adding the Virtual Memory can be done in system configuration.


Tutorial Information & Facts or Implementation

Virtual Memory is a HDD space that uses some portion of it as the memory. It is used to store application data and instruction that is currently not needed to be process by the system.

During the program loading process, the system will copy the application data and its instruction from the HDD into the main memory (system memory). Therefore the system can use its resources such as CPU to process and execute it. Once the system memory gets filled up, the system will start moving some of the data and instruction that don't need to process anymore into the Virtual Memory until those data and instruction need to process again. So the system can call the next application data and instruction and copy it into the main memory in order for the system to process the rest and load the program. When the data and instruction that is in the Virtual Memory needs to process again, the system will first check the main memory for its space. If there is space, it will simply swap those into the main memory. If there are not any space left for the main memory, the system will first check the main memory and move any data and instructions that doesn't need to be process into the Virtual Memory. And then swap the data and instruction that need to be process by the system from the Virtual Memory into the main memory.

Having too low of Virtual Memory size or large Virtual Memory size (meaning the size that is above double of the system memory) is not a good idea. If you set the Virtual Memory too low, then the OS will keep issuing an error message that states either Not enough memory or Virtual too low. This is because some portion of the system memory are used to store the OS Kernel, and it requires to be remain in the main memory all the time. Therefore the system needs to have a space to store the not currently needed process data and instruction when the main memory get filled up. If you set the Virtual Memory size too large to support the intensive application, it is also not a good idea. Because it will create the performance lagging, and even it will take the HDD free space. The system needs to transfer the application data and instruction back and forth between the Virtual Memory and the System Memory. Therefore, that is not a good idea. The ideal size for the Virtual Memory is the default size of Virtual Memory, and it should not be exceed the value of the triple size of system memory.

To determine how much virtual memory you need, since the user's system contains the different amount of RAM, it is based on the system. By default, the OS will set the appropriate size for Virtual Memory. The default and appropriate size of Virtual Memory is:

* 1.5 =

For example, if your system contains 256 MB of RAM, you should set 384 MB for Virtual Memory.

256 MB of RAM (Main Memory) * 1.5 = 384 MB for Virtual Memory

If you would like to determine how much the Virtual Memory is for your system and/or would like to configure and add more virtual memory, follow the procedure that is shown below. The following procedure is based on windows XP Professional.

1-1) Go to right-click My Computer and choose Properties

1-2) In the System Properties dialog box, go to Advanced tab

1-3) Click Settings button that is from the Performance frame

1-4) Once the Performance Options shows up on the screen, go to Advanced tab

1-5) Under the Advanced tab, click the Change button from the Virtual Memory frame to access to the Virtual Memory setting

Then the Virtual Memory dialog box appears on the screen. In there, you are able to check how much the Virtual Memory you set. If you would like to modify the size of Virtual Memory, follow the procedure that is shown below.

2-1) In there, select the drive letter that is used to install the Operating System

2-2) Choose the option that says, "Custom Size:"

Once you choose that option, the setting for Initial Size and Maximum Size become available for you to set. Initial Size (MB) means the actual size of Virtual Memory, and Maximum Size (MB) means the maximum size of Virtual Memory that is allowed to use.

Let's say if your system contains 512 MB of RAM, then the ideal setting for the Virtual Memory is as follows:

Initial Size (MB): 768
Maximum Size (MB): 1500

Once you are happy with that Virtual Memory size, click the Set button from Paging file size for selected drive to apply the setting for the Virtual Memory size. Then click the OK button to apply the setting.

That's where you can manage and configure for the size of Virtual Memory.

Additional Information

* To maintain the good overall system performance, you should be using the default size of actual size for Virtual Memory and the triple the value of the size of the main memory for the maximum size of Virtual Memory. If you find that main memory plus virtual memory is not big enough to load the intensive application, then you will need to add more main memory onto your system.
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