I have a Seagate Freeagent Go external hard drive (250g) that I have never had problems with and has never been dropped, etc. as far as I know. Suddenly my pc won't read it at all. When I plug it in to the USB nothing happens at all (no lights, no sounds, etc.) I tested the USB port and it works fine. I also tried the EHD on two other computers, a pc and a mac, both of which picked it up like normal. So what's the problem with this pc?