Ok I did some searching on this topic and found this post http://www.ntfs.org/forum/showthread.php?s=&threadid=39090&highlight=explorer.exe+restarts It explains that explorer.exe migh restart b/c of overclocking. Which I would believe because my PC is always overclocked, and explorer.exe always restarts on my PC without reason. I also don't get any error messages. The problem is that I went back to stock speed (1.8ghz P4) and explorer.exe still does this. Just randomly restarts, and sometimes I lose programs that were in the systray (which are still running in the background) It's been doing it for six months now. It just seemed to happen out of the blue one day, and has stuck around no matter how man times I do a fresh install of XP. The only other thing I can think of is that maybe my 3d card might be doing it. It's not overclocked, but I did flash the BIOS on my 9500 Pro and it shows up now as a 9700 in Windows. No problems in games though.