Windows 7: Western Digital External HDD - Not being recognized

Hello all. Hoping you can help me out.
You see, here's the problem: I installed Windows 8 Release Preview on my external HDD (which is not in an enclosure.) I was messing around using Windows 8 (booted from the HDD) and suddenly, the cable came loose. Everything stopped. I got a BSOD, and then it shut down. Since then, I have booted into Windows 7, and the device is not at all recognised. It isn't displaying in Disk Management, or Device Manager.
I'm not sure where to go to next.
Please try to help me.
Greatly Appreciated!

Is there not a reset button on the back that you can press to reset it?

Nope. This is my HDD. (see image)

When you said "external HDD" what did you mean as the pic is showing a Internal HDD. Have you tried to plugging this in the Desktop PC and seeing if it can be selected there. Also Download WD Drive Tools, this may get your HD back.

No. It's not being recognised. I think I found the problem. The dock is faulty. Thanks for your help!

You think it's the dock? How did you deduce that?

Because it is a multi purpose dock, so it has USB ports on it. (I tested it, it failed.)
Anyway, it's been resolved.