Have you ever used the hard drive? If not, it may need to be partitioned and formatted. Use Disk Manager (Start -> right-click "Computer" -> Manage -> click "Disk Management" in the left pane). Find the drive in the LOWER portion of the right pane and right-click on it to create a volume and format it.
I tried putting it back in the enclosure and it didn't work. So I got a demo of a data recovery program and it my data is still intact so I can recover all of it, being I have not formatted it. So here in a week or so I am going to buy the program and get my data back.