Hi [MENTION=126473]theserpent[/MENTION],
I am glad to help you out. Based on your post, it may be a hardware issue. I would like to check with you, does it show up in the Disk Management? Is there any error message? If possible, please provide a snapshot and the specific error message.
For the meantime, you may try to run Windows Data Lifeguard Diagnostics software utility, to confirm that the HDD is working properly and there is no hardware issue. Please refer to the link below for Windows Data Lifeguard Diagnostics:
How to test a drive for problems using Data Lifeguard Diagnostics for Windows .
If Its hardware fault, and your product is under warranty, you may proceed for an RMA.
Please check the warranty and RMA services at the link below.
WD Support / Warranty & RMA Services.
For more information about warranty support, you may visit to WD Support / Warranty Services / End User / Worldwide Warranty Policy and Limitations .
Hope it helps.