Hi there jwan25,
It is possible that the issue you are facing is a driver related one. I would advise you to go to Device Manager and uninstall the drive. Reboot your system, plug the drive again and wait for it to install the drivers automatically. If the issue persists, you can reinstall your USB drivers. Check this thread out:
http://answers.microsoft.com/en-us/windows/forum/windows_vista-hardware/error-message-says-problem-with-pnp-devices/d2863cb9-2173-e011-8dfc-68b599b31bf5
You can connect the drive to another computer as well.
If the issue persists, you need to test the drive with either a brand specific or a third party HDD testing tool. The test results will eventually show whether there is something wrong with the drive.
Also, you can go to Disk Management and see how is the drive recognized over there. Depending on that whether the HDD has some damaged partition and/or file system, you can try using some data/partition recovery software.
Hope any of this will help,
D_Know_WD