If you are getting error 0xC800021F on the Windows Update site on your Windows 2000 system, open a command line and run the following commands:
regsvr32 msxml32.dll /s
net stop wuauserv
cd /d %windir%\SoftwareDistribution
rd /s /q DataStore
net start wuauserv
This will register the MSXML DLL file correctly, then stops the Automatic Updates service (so that no temp files are locked), deletes the cache for Windows Update, and finally restarts the Updates service. After you have done this, you should be able to run the Windows Update website normally.
If you’ve been keeping up on any forums, sites, or IRC channels, you know there is a rumor going around about a possible leak of WinNT/2K source code. Microsoft is investigating the claims.
This could be a major blow to open source and to Microsoft. MS, because people may discover new security holes to exploit. And to open source, because if any of this code gets into an open source project, Microsoft will make the SCO lawsuit look like a playground fight. Avoid downloading, because either youre going to be logged, or its a hoax file that is empty (Doom3) or malicious.