unXpected

I had this same problem. And it happened to me twice, once on disk 1 and again on disk 2. What you have to do is clean the disks that are having the problems (or all disks just to make sure they are clean) with isopropyl alcohol (rubbing alcohol). dab it on a clean cloth and clean the disk. then wipe with another dry clean cloth. THEN follow the advice given on post #173798 if you are still having issues. This worked for me and my disks were slightly scratched. Hope I helped!