We actually need some specialist tools for this. Please do all of the following:
Run The System Update Readiness Tool Description of the System Update Readiness Tool for Windows Vista, for Windows Server 2008, for Windows 7, and for Windows Server 2008 R2
even if this tool doesn't solve your problem it creates CheckSur.log
file in C:\Windows\Logs\CBS
folder. Please upload this file. You cannot upload out of a system folder, so please always copy the log files to your Desktop before attempting an upload.
Right, please run steps 1, 2A, 3 (about 15 minutes), 4, 5, and then Step 1 from the top yellow box, but only follow this last one if Integrity Violations were found. Please upload the new sfcdetails.txt from your Desktop. System Files - SFC Command
Now please re-run Windows Update, and let it fail. This puts a failure at the end of the logs, which makes it easier for us. Now please run download and run FireGenUL from here: http://www.eventid.info/downloads/FireGenUL001.zip
Information here: Altair Technologies Ltd.
Copy C:\Windows\System32\FireGenULReport.htm to your Desktop.
If there is still an issue, zip up, and upload CheckSUR.log, sfcdetails.txt, and FireGenULReport.htm.
To zip something, highlight them all > right click > Send to > Compressed (zipped) archive.