Win2K occasionally had an error which MS never fixed - you had to reformat your HD and install new. The error would occur when you right click the mouse. Instead of a menu, you'd get the Dr Watson message that there was an error in EXPLORER.EXE. The system would then restart.
Once you got this error message, the only fix was a clean install. MS never fixed this problem. They went on to WinXP. And charged you for it.
I'm a PC guy for local gov't. Almost every Win2K system we deployed came down with this problem. We moved to XP ASAP.
Sure that wasn't a virus? I have never heard of that one. Did MS issue any info on it?