I will do this and I thank you again.LauraMJ said:If you logged onto the internet, even for a minute, after you reformatted, and hadn't completely downloaded all the critical updates and virus definitions, then it most likely is a bug. When I got my XP, I went straight to the critical updates and virus definitions, nowhere else, didn't even have my email program set up yet, and had a blasterworm before I could finish downloading the updates.
If you have a firewall, turn it on. If it is a worm, it slows the shutdown enough for you to download the blasterworm fixtool from Symantic. I'd suggest finding the fixtool on another computer and downloading it and emailing it to the (possibly) infected computer, or at least taking the troubled computer directly to the fixtool and downloading it to see if this is the problem. With the firewall active, you should have enough time to download virus updates and critical updates.