Also you didn't tell how the disks were made. I find DRAG AND DROP CD creation to be unreliable.
I use SINGLE CLOSED SESSIONS for this reason.
I have been backing up my photos onto CD's. However within a few months the CD's become unreadable. The CD drive doesn't even recognize the CD - it just keeps spinning. This has happened with several different batches of CD's. CD's written by other PC's are fine - this just happens with those created by this PC. Could this be a virus or do we just need to buy a new CD / DVD drive?