I have a different drive, but the same problem. I bought a hdd and enclosure and put it together myself. I had a hard time getting it formatted. I used it successfully for the past few days on USB. I always unplugged it to shutdown and start up or shut it off. I switched to Firewire today, and decided to try a shutdown, and lost everything. When I switch back to USB it shows nothing. Is this an XP problem?? Thanks.
Shane
Today, I rebooted my PC (Windows XP Home SP2)as I do on many occasions, and my external hard drive (a lacie 160GB USB2) suddenly appeared in My Computer as "Local Drive". I have not done anything special to the computer than would cause it, havent formatted anything.
When I try and access the drive, it tells me that the drive isnt formated >.<. In Disk management the HDD shows up as healthy, but with no file system.
Any ideas? I havent deleted anythign, formatted anything.

Chowhound
Comic Vine
GameFAQs
GameSpot
Giant Bomb
TechRepublic