garry35, if you're already using CCleaner, under Tools > Duplicate Finder, you'll find one. Might not be what you're looking for, yet it's a start. Just FYI. Re: https://www.piriform.com/docs/ccleaner/using-ccleaner/finding-duplicate-files
Solway's Plain Duplicate Finder http://www.theabsolute.net/sware/#plainduplicatefinder Nirsoft SearchMyFiles https://www.nirsoft.net/articles/find_duplicate_files.html
I've been using the portable version of freeware AllDup, which allows fine-grained control: http://www.allsync.de/en_download_alldup.php