xp wont update

windows update appears to work normally until install then i get this message Problem: A problem on your computer is preventing updates from being downloaded or installed
Solution: To fix the problem, try installing the updates again. If that doesn't work, use the Troubleshooter to try solve the problem.
have two machines affected .....Please help

1. Sometimes hitting refresh button on the update site will work.
2. Make sure that background intelligent service is running.
-Press Windows+R the type services.msc to bring up the services management console, then browse through services and activate if necessary.
3. Auto update may not recognize your license of XP as valid; so if you are using a hacked copy of XP, windows updater will not function properly.