Windows update error 800004002 vista 64 bit home premium

I continue to get error code 80004002 when I use Windows Update from the control panel of my Vista Home Premium 64 bit computer. NO help from Microsoft. The Fixit program say errors found and corrected but I am still unable to use Windows Update. I suspect a missing or corrupt key in the registery, but have not been able to find any suggestion that works. I have tried safe mode, Fixit, System Mechanic and several other "fix problems" type programs. Where can I get a program that will reinstall the Windows Update? Microsoft says just run the progam and it will update itself. I guess that is okay if the ____ program would run in the first place!