I am running XP Professional SP2 on my home computer. The problem started with the Start Menu not working. I could open it, but whenever I clicked on anything in it, the menu would instantly close without opening what I clicked on. I was able to work around this for awhile. Then after a week or two, explorer.exe wouldn't start correctly on boot up. I would have to end task it, then run it again from task manager to use my computer. Finally, after a few weeks of putting up with that, my computer began instantly going to the login screen upon boot up (I had it set up to auto log on), and whenever I would click on my account to login, The desktop would load, then instantly logout again. Same thing in safe mode, and a repair install didn't fix it. I reformatted the drive and reinstalled Windows from scratch. Everything was hunky dory for a couple of weeks, then the same series of events started happening again in the same order, and now I'm right back where I was before I reformatted it. Any idea what could be going on here? Both times, I was current on my updates. Someone suggested this could be a virus. I've never had problems with viruses or spyware before.