If the harware is in perfect order, the 'file system structure' may be damaged. They will sometimes unlock a stuck disk controller by simply issuing a subtly different sequence of startup disk commands. If the hardware is semi-intact, you may try to connect the device to different computers running different operating systems (LInux, Mac, Windows XP, Windows 8).
This is only possible if the hardware is intact. Hello 'Help Me', if the data on the disk is really important, the first thing you need to do before you risk deleting anything is to make a *raw* copy, also called an image, of the disk.
