Not Deleting Files in Vista's Root Folder

Trying to simply delete a *.tmp file from Vista's root folder. I've tried everything I know from labeling the folder "C:\" and "%rootdir% to "systemdir". Nothing works. When I move the tmp file to "test" folder and change my argument to "FileKey1=C:\test|*.tmp", it works like a charm and deletes the tmp file immediately. Yes, I have full admin permissions, etc. Seems to me somehow CCleaner is not cleaning anything out of the root folder on Vista, no matter what. Can anyone else duplicate this issue ? I have used CCleaner with a custom winapp2.ini file for a couple of years now, so I don't belive I am overlooking the obvious... THANKS ! !

Problem resolved for Vista, and it was not a bug in CCleaner. Found this KB article on the MS website. Turns out you have to CREATE the

%rootdir% environment variable on Vista. It's not already there as in previous versions of Windows. Once I created it, following this KB article, CCleaner wiped the TMP files out of my C:\ folder like a charm. Hope this tip saves someone else some agony.

KB article: http://support.microsoft.com/kb/931715