Because of Windows Autorun & Autoplay feature viruses could easily get into a computer system through USB devices by modifying the Autorun. Inf file (a required file for auto run).

The simplest solution is completely disabling Autorun & Autoplay function in Windows, by manually or automatically. However, in case your USB stick was infected, distorted, corrupted or in any way became inaccessible by malware here is a handy utility, Autorun Injector, to restore it in an accessible state and help de-corrupt the entire drive.

Autorun Injector (similar tool – Panda USB Vaccine) gives the user ultimate control over their removable drive's Autorun.inf file.

With this utility you can do the followings:

1. View and delete Autorun.inf file from a USB devices like pen drive
2. Create new Autorun.inf file
3. Protect Autorun.inf file

Autorun Injector is portable, weigh (just 270Kb), clean (check here for report) and works perfectly with Windows 7, Vista and XP. You can download it at source.