After reading 3 (and counting...) topics on Internet Cache not being cleared, I decided to test it myself and indeed, it isn't getting cleared. Something to do with the new version.
EDIT: I just restarted CCleaner and it worked. Strange.
EDIT: After numerous tries. I am now 99% sure its working right.
Had you made certain the Firefox.exe process wasn't still running?
Only Microsoft Office and Microsoft Paint was open.
P.S. All seems to work now.
Only Microsoft Office was open.
Firefox doesn't necessarily have to be open for the exe to still be running, especially with some extensions which have been known to keep the Firefox exe running long after Firefox has been closed. Thats why I specifically asked if the "firefox.exe process" was still running
Well, I did not check so that was probably causing the problem. Explains why everything suddenly works fine.