When you plug in a USB flash drive in your PC with Windows Vista or Windows XP, it will seek for "autorun.inf" and run an executable file. Sometimes it's safe, but you cannot be sure that an executable file is not a malicious software. You can disable autorun, but what happens when you doubleclick the removable disk? Your guess is right, the executable file will run immediately. If you want to prevent "autorun.inf" from running from any USB flash drive, just install USBDefender and restart system.

Another way to disable "autorun.inf": start disable.reg and add information to the registry.

How to see that USBDefender or disable.reg are working? Copy this two files to your USB flash drive and doubleclick the flash drive button.