You might read the thread at the below link as it sounds like it might be similar to what you have going on.
http://www.eggheadcafe.com/software/aspnet/30524975/cant-run-windows-update.aspx
If that doesn't work I would send an e-mail to Micro$oft and see what they say. Here's the link:
https://support.microsoft.com/oas/default.aspx?LN=en-us&gprid=6527&acty=Start&ctl=Region&wf=Workflow&x=11&y=8
Cheers!
Bill