If it has at any time been on a PC then it will be corrupted. I found that out the hard way. Just a shot in the dark...otherwise make sure you're using the most recent version of DiskCopy or ShrinkWrap, and if you're only trying using one program, try using the other. I had a disk image once that would work fine with Disk Copy, but got an error with ShrinkWrap. Hope this helps.