Board 8 > What's up with my hard drive?

(+) Yeah! (+)

So I need some help. I have an external hard drive that I bought awhile ago and until recently had only used it a handful of times to transfer all my large files from my laptop.
The issue Im having now is that no devices seem able to pick it up. When I plug it in, the light comes on and I can feel it working but Ive tried a few different devices and nothing seems to register it. Any idea why this is happening and what I can do?