Hi,
This is a common issue with WD drives.
Right click on “My Computer”
select “Manage”
Then go to “Disc Managment” and you will see that both drives are displayed… but one of them will have a little “i” next to it in a white bubble…
Click this bubble and you will be given the option to enable the drive (there will be a device I’d conflict stopping them from both being active at the same time)
Thn i would seta new drive letter, give it a new name and format it 
Then bingo you’re done.
Hope tht helps.
