My Passport 500 GB

Bought this about 2 months ago. Used with two different computers (Desktop running Vista, Laptop running 7). Everything was working fine. Now, when I plug it into either computer, the light doesn’t turn on, it doesn’t make any noise, and windows acts like nothing’s there. Any options at this point?

Sounds like a power issue. Is it  a powered or USB powered drive? If USB powered try a different cable if possible.