found this web - yet to try out, basically it claim there is a virus called Vundo .
also found this..from here..
1) Open CMD prompt as Administrator
2) Enter the following: takeown /f C:\Windows\winsxs\pending.xml
3) Enter the following, and type in your username in the designated
place: cacls C:\Windows\winsxs\pending.xml /G
4) Go to C:\Windows\winsxs\ and rename the pending.xml file to
5) Run Windows Update again, and you should be all set!
read here, many claim that system restore will get rid of the problem..i think the only thing i did was uninstalled some of the games..
how to do system restore in vista, read here..
tried restore to the date of last window update, also not working, then finally need to restore back to factory image. Now I can do window update. But need to start install back all the software I have before, it is pain.