A number of pc utility programs offer the feature of finding and deleting duplicate files. Ashampoo Uninstaller version 5, which I like very much, found over 100,000 duplicate files. The list is daunting, and you have to check each separately in order to delete them. There are a lot of files to go through, but frankly this seems risky. Is deleting duplicate files safe? Obviously there must be some risk involved because the program does not allow you to "choose all" and do a mass delete.