A few years ago my WD drive came up unmountable. It turned out the problem was the encryption board. It seems that all WD data is encrypted by this board that sits inside the external box bit outside the drive. It usually encrypts and decrypts transparently, until a user wants to pay to password protect the drive. When the encryption board goes bad you are stuck: either pay $1000 to get your data unencrypted or but a new drive and substitute the encryption board, if you know how to do that. I’ve avoided WD ever since then. On the phone they tried to deny the encryption, but it was a lie.
If you make any changes in the hardware of the drive then it would void the warranty of the drive, I will suggest you to contact WD support to get better assistance.
Refer the link provided below for contact details.