Back when disk drives were huge in size yet minuscule in capacity, duplicate files were like coronary blockages, a growing problem that could crash the system at any time. Programmers responded with duplicate file finders, which had a bad habit of misidentifying duplicates. Today, duplicate files are more like stubborn body fat, your PC's "love handles": Not exactly welcome, but too much trouble to remove. Good thing the programmers aren't taking it lying down! For example, there's AllDup from Michael Thummerer Software Design. It's a free duplicate finder that seems to have an answer for every question, at least those pertaining to finding and rooting out duplicate files, wherever they hide.
AllDup's default interface displayed our drives and folders with checkboxes to select them for searching. Log and Profiles buttons are handy if, for instance, you regularly upload a lot of snapshots from your camera. We were impressed by numerous options for configuring, filtering, and displaying search results, most customizable via buttons with labels such as Add, Enter Text, Replace, Edit, Open, Remove, and Check. Despite its extensive filtering and targeting options, AllDup proved pretty easy to use. Starting with the Pictures folder on the C drive, we applied it to several drives, finding not only duplicate images and media files but also multiple copies of some programs and updates in different download folders. As with all responsible duplicate finders, it can move files to a safe folder for review before you delete them. AllDup has some nice extras, such as the ability to add an entry to Explorer's context menu, to designate external programs like Word for tasks like file comparison, and to specify plug-ins that the preview pane will use to display certain file types, such as media files.
AllDup seems to have things covered when it comes to comparing files by name, size, extension, and attributes--even byte-by-byte Content analysis--as well as excluding things you want left alone. Of course, all the options in the world are useless if you don't take the time to go through them, but we found AllDup's settings easy to handle. AllDup shows that free duplicate file finders have come a long way.