Wizard Transfer update problem

I created a back up file of my computer using XP (just the standard issue). When I try and restore the back up files the computer does not recognise them. The dialog states that the location does not contain the files, but it does. There are 7 IMG (DAT) files around 2GB each. They are located on an external drive under a file called USMT2.UNC. There is also a “status” file of only 1KB.