Hello Microsoft, in your daily visit to my site, do you mind telling me what is wrong with WindowsUpdate?

From different machines XP/2k the scan stops at 0%, so infact it doesn't start at all

It's not just me I've received more emails from people with this issue.

Also if you install win2ksp3 the Windows Update program breaks with the error code "0x800A138F", then you will need to execute the below procedure to fix the problem.

RESOLUTION:

go to Start, then Run Type in "regsvr32 iuctl.dll /u" to unregister the program
Find iuctl.dll and iuengine.dll and delete all instances of them
Here is an article in WinNetMag with more on this issue:
http://www.w2knews.com/rd/rd.cfm?id=020826RN-W2K_SP3