Nero 6 OEM backup disk not accessible

I backed up my c: drive with Nero 6 OEM, using CompUSA dvd+rw disk.
The O.S. trys to read the disk when inserted to no end. When I try to restore the backup w/Nero I can not access the .nbi file on this disk. Get error - E:\ is not accessible.
A device attached to the system is not functioning.
I've done backups before using CompUSA disks w/ no problem.
Using Isobuster I can see the .nbi file, but get that the Joliet, ISO9660 path table, and directory couldn't be read properly. There is a lead-out so the disk must have finalized. Does anyone have any ideas on how to recover the data on this disk?