500 GB Hard Disk unresponsive

Hi, due to my limited IT skills, I would like to entreat my fellow mates to kindly look into my problem.

i tried many times with solutions given in the net, yet, i failed to restore my external drive.

when i double left click my drive icon, it says my drive is corrupt and unreadable, my 500 GB external drive says, it needs to be formatted. with right clicking on it, properties, tools and then check the drive, it says drive cannot be accessed.

with cmd types in run command, it says, the operation cannot be done with raw drive.


i am using Dell laptop with windows 7. Kindly help me !!