I've googled this and I now I am not alone in the problem. It just happened yesterday. Its not my machine but I assume its Vista Service Pack 1 issue.
I've tried to reboot in safe mode, last known good configuration, Start up Repair, with this Windows recovery disc (http://neosmart.net/blog/2008/windows-vista-recovery-disc-download/
). All that happens it that it either continues to the Update Screen and enter infinite loop or it stalls on the Windows Screen (the one right before the welcome screen). I have since removed the hard drive places in a USB dock and am using my Windows 7 machine to access it. I've tried renaming the "pending.xml" file, but get the whole ""You require permission from SYSTEM to make changes to this file". I then tried following instructions at http://social.answers.microsoft.com/Forums/en-US/w7performance/thread/800326ee-5d55-4ef9-ac67-b5e1669989a5
but now I can't change stuff because I don't have permission from myself (not my admin, my only user).
Um... what to do now? I don't have a vista disc. Its on the partition. But I don't know even now how to reinstall everything to factory standard if I can't get past either of the screens mentioned above. I've saved what I need via the USB dock.
Your help is appreciated,
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