External hard drive isn't lighting up or being detected? Urgent!

Hi,
I have had my 1.5TB Desktop External Hard-drive for... a year or two? And I have had the occassional problem with it, but now I can't fix it myself. It's WD and as I said, holds 1.5TB. I have 220GB< worth of irreplaceable stuff and I need help!
I lost it's real power and USB cable, but I have been using substitutes that have been working fine and have been for the whole of this year. The light on it lights up half way when it's plugged in (and it's visible at the moment with it plugged in) and then flashes very brightly when connecting, and remains solid when connected. I haven't used it in a couple of weeks and I think it might have magnets in it because when its working sometimes I swivel it around and it has water in it (it doesn't.) I had it under a light-medium tin that was aluminum, but it was easily half the hard-drives weight. When I plugged it in to power everything was fine, then I put the USB in, it flashed, but then my computer didn't let it through? Now whenever I try to plug it into any of the 3 jacks I have, I doesn't even flash. Can somebody help?!

Hello Mochan and welcome to Seven Forums.

When you say things like:

I have had the occassional problem with it, but now I can't fix it myself.

and

I lost it's real power and USB cable, but I have been using substitutes that have been working fine and have been for the whole of this year.

and

. . .when its working sometimes I swivel it around and it has water in it (it doesn't.)

it almost sounds like your external hard drive has either died or is about to die. Is it being recognized in disk managment? If you post a screenshot it may help to diagnose the problem.

How To Access Disk Management in Windows 7

How to post a screenshot:

Screenshots and Files - Upload and Post in Seven Forums

Thanks for your consideration - but I have concluded that it's a broken USB cable. I plan to continue to use it though, and when I hold it in a particular position it will still work. The solution would be a replacement chord, but why not use it to the very end?
Anyway, thanks! Other than that, the HDD is still fully functional and transfers are still fairly fast ^^

Thanks for posting back.

No problem. Thanks for your consideration and I'm sorry it was so bland T.T