What appears to be happening is that one of the files in the folder is still being invoked by windows and has locked that file. If you go into the folder and delete the files/folders individually you will find the culprit to the problem. Then do the following:

1. Perform a cold boot on your system.

2. Check the task manager to insure there are no loose firefox processes running, especially the file you couldn't delete from the folder. Note that I said processes. If you find any do an "end process" on them.

3. Do a Windows Search for all files and folders containing "mozilla."

4. Delete any items found but be careful. Mozilla thunderbird will be caught up in the search.

5. Do another cold boot and manually check to see if the folder is gone or that you can delete it..

It says can't delete profiles in the mozilla folder. How do I delete the profiles folder in the Mozilla Folder?

Do you still have a Mozilla Firefox folder in C:\Programs Files?

You can try to boot the computer in Safe mode by pressing F8 on the boot screen to see if that allows to delete that folder.

See also http://ccollomb.free.fr/unlocker/ - UNLOCKER 1.8.7 BY CEDRICK 'NITCH' COLLOMB

I do not still have the folder.