Have you tried cleaning the disk for finger prints?
There is a certain way to clean disks to prevent scratches from damaging the data, always wipe from the center of the disk out-ward, not in a circular motion.
Mild dish soap and water is fine to remove oils, dry the disk off with a non abrasive cloth and wipe out-wards from the hole all round the disk till it is dry.
If the disk contains noticeable scratches, there is a method of using smokers toothpaste mixed with water and carefully wiping out-wards towards the outer disk edge only where the scratch is, try not to wander from the scratch area, because you can create new damage to an unaffected area of the disk. Wash off all excess toothpaste and let the disk dry.
If you've ever made the mistake of writting on the disk with a ball point pen, you may have damaged the disk beyond repair, the printed side of the disk is closest to the data than the clear side.
Hope this helps. Good luck.
Edited by MrBruce1959, 07 July 2010 - 10:45 PM.