Go into Windows Update and look for any update marked "Failed".
Click on "View Update History"
When you see the update history, click on the link as though you were going to download the update.
Don't download, but instead, click "Run" and run the update.
During the update you will get some errors - JUST CLICK "Ignore" and go by the errors.
The update WILL complete, although history will still show "Failed" for a time.
Next time Windows Update runs, it will see that the update is done, and will mark the given update as "Successful"