That's the beauty of Windoze!!!
That error can be caused by any number of things, but first and foremost could either be a software conflict (a conflict between Windows and a program you may have loaded) or a memory error (meaning that if you let Windows run for too long, it clog your RAM full of useless junk that eventually causes it to crap all over you, and sorry about your luck if you didn't save that Word file that you've been typing on for the past 4 hours!!!). Explorer.exe is the main program for Windows. In Windows 2000, if you open up the task manager, and close Explorer.exe, your desktop will become non-existent, except for your cursor and your wallpaper.
Some questions to ask you:
Did this happen shortly after you loaded a new program on your system?
How long has it been since you did a ScanDisk, defrag, and disk clean-up?
How long has this machine been loaded?
Which, if any, service-pack do you have?
Do you reboot your machine often? Or do you let it contantly run?
And the last question I have for you is this:
Why are you running Windows when Linux is such a better OS? ;-)
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