Did you run the DOS version of the tool? As experienced by some users the DOS version was able to repair the bad sectors, when the Windows version failed to.
In any case, as essenbe says, your first priority now is to recover as much data as possible, before trying out anything ( if you consider that you do have some important data you may not like to lose
First use Recuva and check whether it can do the job.
If it fails, the next option I would try is to access the drive with another OS and copy the data if possible. Lucid Puppy way to recover files from a non-bootable computer
(In your case the copy process will be from the faulty external drive to your C drive or any other internal partition - space permitting - or to another external drive.)