DUPLICATE FILE FINDER

HOW TO USE DUPLICATE FILE FINDER

See here

https://www.piriform.com/docs/ccleaner/using-ccleaner/finding-duplicate-files/using-the-file-finder

You must use this WITH EXTREME CAUTION and be really, really sure that a file is a duplicate before you delete it.

THANK YOU FOR THE INFORMATION. IS THERE ANY OTHER THING I SHOULD BE AWARE OF? HOW WOULD I KNOW WHICH FILE TO KEEP OR DELETE?

Please stop talking in all caps. It's hard on the eyes and is considered to be very rudely shouting.

The simple rule for the duplicate finder (and the registry section) is ONLY DELETE IT IF YOU KNOW YOU DON'T NEED IT

Example 1 (safe to delete): two photos files: one on the desktop; one in the my pictures folder. Both are named dc0000567 both are exactly alike when viewed in image viewer. One can assume in all likelihood that they are the same and can be deleted.

Example 2 (delete with caution after research): two files; both named NSF10-3.dll. one resides in c:\program files\HP\Drivers; the other was found in c:\windows\system32\drivers\HP. I personally wouldn't remove either of the files, but after reading a little on the web you may discover that the program files one is only a drop point made during installation and can be removed without ill effect to the HP device it belongs.

Example 3 (do not delete): The search brings up a file duplication of program.exe. one is in c:\program files\random program, the other in c:\program files\random program\safety bin. You get on "random program"'s website and find the when somebody deleted the "safety bin" folder wholesale the program broke and was uninstallable, the repair thread lasts 10 pages and ends in the original poster having to receive a specially crafted zip file from the developers to fix it. I would definitely not delete the duplicate in this case.

As you can see, for the most part, you should take a long time educating and then deciding for yourself what to remove, we can't really do that for you.

To continue with Nergal's above examples:

Use a file hash/checksum tool such as NirSoft HashMyFiles (freeware), or some other one that you prefer. Make sure at the very least that the MD5 or SHA-1 are 100% identical. When in doubt leave stuff alone you aren't sure about.

I personally think this is a dangerous shoot yourself in both feet tool that's integrated into CCleaner which was unfortunately requested by some users. If you aren't diligent with insuring what's a duplicate and what isn't it can be very damaging. For instance completely leave system files like .DLL, OCX, etc., well enough alone because messing with them will eventually break something important either an installed software, drivers, or Windows itself and regaining a minuscule amount of disk space isn't worth the trouble deleting the wrong thing can cause. Edit: In fact, I'd stay completely away from the Program Files and Windows folders altogether!