If you can feel the drive spinning then the USB port is working fine and you are more likely looking at a software issue. Resetting the BIOS won't do anything either.

1) Right click My Computer and goto manage.
2) Goto Disk Management

Can you see the drive in there? (Please don't format it. That's not good advice I'm afraid)

There's a chance you may have put another usb device such as a memory stick into that port and it has taken the drive letter that the external drive wants to use.

If you can see the drive in Disk Management, right click on it, and select Change Drive Letter and Paths, then click on Change. Select a drive letter that is unused and click OK. The USB drive may now be accessible.

Personally I like to boot into a boot CD such as Hirens to eliminate any Operating System glitches. If it shows up in the boot CD then you would be looking at tweaking the registry section for known mounted devices (assuming you didn't see the drive in Disk Management).