Inability to access your data stored on the data storage device could be caused by many reasons, from those that are easy to fix to those which are completely impossible to fix. If the damage is irreversible then data loss will occur. The causes of the failure of your hard drive or CD-ROM drive could vary from a bad connection due to a loose wire (which is easily recoverable) to damage to the media itself, which could still be recoverable in many cases. As in the medical profession, the first .