This is part of a process on one by one taking a group of older external drives, each with hundreds of folders on them and 250,000+ files on them and slowly moving files from all of them, in a process to end up with one much larger drive having at least on copy of every file I own on it. So the following would be on stage of this process: On external drive ONE I have many folders and files. On external drive TWO (the giant drive that will eventually have copies of all files), I have many files and folders on already. I need to find a program or some other way to find (and move) the files that are on drive ONE but that are not on drive TWO. I then want to move them to one large new folder on drive TWO, no matter what type files they are. There may be some files with duplicate names but they will, in most cases, have different sizes or dates on them. The method I use would have to be able to look at those file attributes also (name, size, date). It is not critical that I have copies of every single file end up on drive TWO (this may happen when a file gets overwritten in the process when it DOES happen to have the same name and size as the file overwriting it). My goal is not to end up with any drives synchronized. I just need to end up with VIRTUALLY (almost) every file I own on drive TWO. Each drive has hundreds of folders and maybe 500,000 files on them. All files are media and document files only. I am not working with Drive C. I am using Windows 7 Premium Home. Thank you for any help.