In CCleaner there's an option under the menu 'Registry' called 'Unused File Extension' which (if checked) lists all the filenames for which their extension isn't associated to any application. This should *only* apply to filenames and not to directories. If you have a directory with a dot (say 'test.xyz'), CCleaner will list it among unused file extensions (the unused file extension being 'xyz' of course).
You can test this. Make a directory (or a *folder* in the Microsoft Windows term) named 'test.xyz', access it (double-click the folder) and close it. Then run CClener with the option 'Unused File Extension' (in the menu 'Registry') checked. You'll see that this folder has been found by CCleaner as an unused file extension. All we did was just give the folder a dot in its name, but CCleaner assumed that the 'xyz' (in 'test.xyz') is an extension.
Please put a mechanism in CCleaner that would distinguish between files and directories. If CCleaner finds a directory, then the 'Unused File Extension' option should ignore it and not further deal with it.
The issue isnt so much that CC finds the folder and deems it as an unused extension. Its more a matter of Windows adding the name to the registry as a 'used' file extension. CC scans the file types under classes root and determines there isnt an associated application for opening .xyz
So really CC has no way of knowing where the .xyz file ext came from. Be it folder, file or otherwise. CC simply found the registry entry for .xyz and dosent see an associated application. The real issue... Why is the file ext being added to the registry in the first place? Use a period in any file or folder name and its deemed an ext and added to HKCR. So it seems CC is doing its job to the letter.
We cant expect CC to scan the registry then scan all drives and partitions looking to see if the file ext is being used and if so, is it a file or folder? Scanning would take forever and whether the ext is found or not still dosent mean that the ext is in use, an orphan or false positive etc.
You're right. It's the crappy OS that is having the problem. I think I'll switch to Linux some day because I like perfection and Windows OS is far from that. Thanks for the reply.