Hi there brianjohngerke,
I would agree with Ralston18.
You need to attach the drive with another USB cable to a different port or even system.
In case the issue persists, you need to go to Disk Management and see if the drive is recognized over there and how.
In case it is, but has damaged partitions/file system, you will need to use some data recovery software in order to retrieve the data.
In case it is not, then there is something wrong with the connection, enclosure or the HDD itself. In that case, it would be nice to attach it internally via SATA.
Also, you can try to test the drive with some of these:
http://www.tomshardware.co.uk/forum/282651-32-best-diagnostic-testing-utility
Hope this will help,
D_Know_WD