A few of my friends had already been infected by this virus. It is a very wide spread virus. The patch had already been released weeks ago. If you got infected, you deserved it. For god’s sake, be a responsible user and keep your Windows up to date.

How to Tell If Your Computer Is Infected
If your computer is infected with W32.Sasser.worm, you may see a dialog box with text that refers to LSASS.exe. Some customers whose computers have been infected may not notice the presence of the worm at all, while others who are not infected may experience problems because the worm is attempting to attack their computer. Typical symptoms may include systems rebooting every few minutes without user input.

For more information on this virus and how to remove/prevent it, visit this Microsoft site.

To have enough time to do so, you need to disable the shutdown of Windows by any application. Go to Run, type “shutdown -a” without the quotes.