typically that only works if the circuits are overheating, but hey its worth a shot.
SS-
if your file recovery program doesnt work, check out spinrite
if that doesnt work, it's difficult to say what will.... oh yes, take it out of the external drive case and plug it in to your desktop machine if you have one before doing spinrite.
...just a note, for when you do take the drive out and put it in your desktop, if you SWAP your desktop drive and this one, dont boot it into windows... would likely bluescreen. just do the spinrite, or add it as a slave drive.