Some of viruses are coming from USB Flashdisk, it's the famous media where the programmers speard their electronic viruses, important thing you can do to prevent them, you can disable USB Flashdisk autorun. So after you plug the Flashdisk in, the computer will not automatically read the autorun.inf -the file that could read system data inside the Flashdisk, including viruses-.
You can disable Flashdisk autorun by these following instruction.
WINDOWS 95/98/ME
1. Access the System Properties Dialog. Using Control Panel: My Computer: Properties or Explorer: My Computer: Properties.
2. Select the Device Manager tab.
3. Select the CD-ROM folder.
4. Select the entry for your CD-ROM drive.
5. Select Properties.
6. Select the Settings tab.
7. Turn on or off the Auto insert notification option.
8. Select OK.
9. Select OK
WINDOWS NT/2000
1. Start RegEdit (regedt32.exe).
2. Go to HKEY_LOCAL_MACHINE/System/CurrentControlSet/Services/Cdrom.
3. Edit the Autorun value to ‘1' to enable autorn, and ‘0' to disable autorun.
4. Close RegEdit
WINDOWS XP
1. Open Windows Explorer by pressing the Windows + “e” key.
2. Right-click the desired CD-ROM and select Properties from the menu.
3. Select the AutoPlay tab.
4. Select each item from the pulldown list and for the Action to perform, select “Take no action” to disable autorun, or pick the apporpriate action to take if enabling autorun.
5. Select OK.
More instruction.
Autorun can be enabled or disabled for all Removable media types, such as a floppy or Zip disk. Windows systems are configured to enable CD Notification, other removable media are by default disabled.
The System Properties User interface only exposes the CD Enable or Disable selection. The setting reflected in this dialog makes an entry in the System Registry. It is in this same location that other media types are configured.
Notes:
1. Modifiying the Registry is not for the inexperienced user. Anyone will tell you, be VERY careful.
2. The modifications made in this case use Hex not Decimal numbers. If you are unfamiliar with the Registry or the characteristics of base numbering and Hex, studying these topics prior to making these modifications is advisable.
To Modify these Registry Settings, Use Regedit and navigate to the following Key:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer\“NoDriveTypeAutoRun”
The default value for the setting is 95. Change the first byte to 91. Restart the computer to make the new setting take effect. You may have to right-click on the floppy and choose AutoPlay from the menu to see the AutoPlay behavior.