I've got a Vista Business SP2 machine which is on a domain and receives updates via WSUS. A batch of updates about a month ago resulted in 'Updates were not configured correctly, reverting changes' on boot. I've re-registered the DLLS associated with Windows update and this didn't work. I've looked through the list of failed updates, all give the code "800F0826" which according to MS website just means there was an error with another update, keep looking through these errors until you find a different error code. I've done this and found update KB969084 failed with error 80004002. I had the same issue on another PC and discovered that manually installing the update then following Windows Update seemed to work, however, when I try for this machine I get the message 'This update does not apply to your machine' I'm clicking through from Windows update and being taken to this page: http://support.microsoft.com/kb/96908 I'm then opting for the following link: Download the Update for Windows Vista for x86-based systems package now. Since my system is 32bit. This is when the 'This update does not apply to your machine' error pops up. I'm not sure what to do next - Windows Update is still failing. Any help much appreciated.

Thanks Magon Liu, I'd already done method 1 so I went for method 2, the standard fixit did not work so I went for the aggressive fixit it, this did not work either. I was in the process of downloading the Readiness tool (fairly large) when I decided to try downloading the failed update again just for the hell of it, I began installing this whilst the Readiness tool was still downloading, I restarted and it seems to be okay now! The 39 updates it had to do eventually went through then a restart and 9 more, a restart and 2 more and a restart and 1 more. Phew. All in time for our internal 'Patch Thursday' which is today. Thanks for your help.