I had this drive for like 8 months now, its running over Firewire 800 and it all worked perfectly up to now. Like 2 days ago the drive wont mount anymore over firewire. I thought it fried and hooked it up through USB and it works perfectly. I remember like 3 months ago I had the same problem so I unplugged everything from the iMac in the back and let it sit there for 5 mins and then it was fine. I tried doing this like 2 times already and nothing, it still wont mount. The disk doesnt show up in Disk Utilities or anything. This is my time machine back up drive, and I need to back up ASAP. I dont know what to do. Some are saying I must format my drive all over again. Do you guys know what I should do. I checked to see if my iMac updated and it showed one update on oct 5th, I dunno if this caused it. I updated the OSX today and still nothing happened. Any help would be appreciated. Thanks guys!