I'm on Windows Xp and before it worked fine, I plugged it in and right away it would show up in My Computer as E: and F: drives and "autoplay" would come up. Now when I plug it in, my computer shows the notification like it is plugged in, but doesn't show anything in My Computer, doesn't let me run the drives, and they don't show up in Disc Management.
Any help would be greatly appreciated as it is my backup drive with everything important on it.

Computers & Internet - Vantec - Nexstar - NexStar-3 External 3.5inch SATA&USB2.0 Hard Drive Enclosure...