k i just had this error and i tried everything i could do (without re-installing) and nothing.
so i just had to re-install vista (i did not reformat i just installed it) and it seems to be ok now i just need to get all my files and settings back and remove the old install.
thats where i have a question.... could i just go into the windows.old folder and just delete that folder? or what is the best way of doing this?