17 R5, issue adding 2TB M.2 SSD

Hi,

I’m hoping that someone here will be able to help me with a problem that I am having with my Alienware 17 R5.

I’m trying to add another M.2 SSD to the 17 R5 but am having some issues getting it going. It’s a Western digital 2TB M.2 that I had running in a external enclosure but won’t show when I install it in the laptop.

I decided to swap over the slots the SSDs were in to see if that would make any difference, which it kinda did, the laptop now saw the 2TB WD (in the Bios) but was not booting as the 128GB drive wasn’t being seen now. I then swapped them over again, the 128GB was back up & booting but the 2TB had disappeared!

I’m getting to the point now where I can only think of few things that could be going on is the SSD-2 slot is faulty as it doesn’t recognise drive.

Can anyone help?!

Thank you in advance

Paul