In Win 7, if a user changes the permissions for the User folders, the paths recurse, apparently until the character limit of the path is reached. This apparently creates very long running times for programs such as RegVac, and various other problems as well.
The helpful folks at Microsoft advise reinstalling Windows and all applications, and then sin no more. They seem to regard this problem as fully deserved by those who dare to mess with Windows permissions.
I confess that I have sinned -- with several Windows machines. I've tried various fixes, none of which actually work. I would rather not reinstall everything.
Any advice, helpful or otherwise, would be appreciated.