Several months ago I was having problems with my optical drive so I bought a new one and replaced it. Today I tried to open some of my back-up DVDs and CDs, and it looks like it's opening fine - I can see the folders and files, but when I try to open any one of them I get a message on my screen that says, "Windows - Unknown Disk Format" There is a red dot with a white "X" and the message, "The disk in drive D: is not formatted properly. Please check the disk, and reformat if necessary" Then I have a choice of 'Cancel' 'Try Again' or 'Continue'. When I open Nero to burn something on that disk it opens it as if it was a blank disk with no information showing. But when I open it the normal way I can at least see the files and folders. How can I open these files and folders? I hope all this information is not lost!