Ever had the problem where Windows Update freezes during the download phase and won’t continue?
Check to see if BITS is running. If not, and it WON’T start..read below

Try deleting the downloader cache files!

I’m not going to include XP users because:
1. I can’t remember the exact path
2. You’re still using XP, you’re a bit behind.

For Windows 7 users, the downloader cache/queue location is c:\ProgramData\Microsoft\Network\Downloader.
Inside this folder are .DAT files, remove them and see if BITS will now start thus, enabling Windows Update.
Note: This has only been tested for people using the Microsoft site, it “should” be the same for WSUS, but I can’t guarantee it.