|You should be able to repair the data damage with one program or another, if there's nothing else out of whack, unless you're dropped the external drive in which case all bets are off. |
Troubleshooting USB device problems including for flash drives, external drives, memory cards.
See Response 1:
Check that out first.
Rarely, not all the ports on the back of a desktop case may be able to supply 500ma each.
If you have a desktop computer, Note that I answered a Topic on this site recently where a guy had an external drive, which does require the full 500ma, connected to a port on the back of a desktop case - it would not work properly when a webcam was in the port next to it, but it worked fine when the webcam was unplugged. Ports on the back of a desktop case often have two ports connected to the same USB controller module that are ports one above the other - you could try connecting the cable to one of those and leaving the other un-used.
Once you're SURE you have it connected to (a) USB port(s) it should work with for sure (you MAY need to connect to TWO USB ports on the computer) you could test the external drive.
Seagate's Seatools will test any brand of hard drive.
Do the long test.
You must use the Windows version of Seatools in order to test a hard drive when it's in an external enclosure.