Problem
Running Windows Updates on XP and it has downloaded a bunch of updates but refuses to install them. It just whips through them all, announces they've all failed due to a problem on your computer, and offers to dump you into a useless "troubleshooter".
Diagnosis
There is a WindowsUpdate.log file in your %winnt% directory (usually C:\Windows). Look through that.
Solution for 0x80004002
Press Start, then Run.
Type in
and hit enter, you'll get a little popup saying DllRegisterServer in WUAPI.DLL succeeded.
Repeat that step for these below..
REGSVR32 WUAUENG.DLL
REGSVR32 WUAUENG1.DLL
REGSVR32 ATL.DLL
REGSVR32 WUCLTUI.DLL
REGSVR32 WUPS.DLL
REGSVR32 WUPS2.DLL
REGSVR32 WUWEB.DLL
Then try Windows Update again.
This worked for me. Allegedly it will work for error 0x8024400D as well.
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