Not reading the external drive

I have a Mac White Book that is no longer reading the external drive. Up to last Saturday it read it fine.  I have tried putting into a different computer and it does not recognize it there either. Help!

Hello,

Does the WD external drive spin up?

Can you hear WD external drive making noise?

Have you try connect either Firewire or USB cable?

Does the LED on the from of the WD external drive lit up when powered? if not, try a known good 12V 1.5Amp AC adapter.

Hello,

Answers to questions: Yes, sounds like the WD drive is firing up and running, light comes on too. It is being connected via a USB cable.

Is it your WD external drive My Book or My Passport? Does it use 12V 1.5Amp AC adapter? How long is the USB cable? about 3 fts or 6 fts If it is 6 fts, try use it with a 3 fts or shorter. Would it make any different. If you have tried all of suggested above but still not making any good progress. You need to contact WD technical support for further help. www.wdc.com/support