I purchased 3 8TB WD EasyStores, ran hard disk sentinel tests on each, then shucked them all. I am able to see and use 2 of them in W7, however the 3rd is not visible in File Explorer, diskmgmt, or the BIOS. However, if I take that one out, and connect via the external enclosure, it reads just fine.

Looking for some advice on how I can use this drive internally instead of externally.

Can provide more details on request.

Try another sata port and or sata cable. Additionally I'd update the bios as it maybe a controller bug.
Oh and you may wanna try using all sata 2 ports (3gbs) vs the sata 3 (6gbs) ones on boards that have both.

This post was edited by King Atrhur on Apr 19 2018 12:58pm

I forgot to mention j did swap sata cables, power, ports. Same jssue persists, all other drives fully functional.

Will check my board tomorrow, it is the Asus Z97-a.

Have ALL drives in the 6gbs OR 3gbs sata ports not both is what I mean so were clear. (ideally the sata II intel based ones)
On phone remote'ing into my pc so I don't care to google your board but it will have both kinds I'm sure.
Get back to me after you have tried this, if you use more drives then you have support for on just one of the interfaces then you may be shit out of luck without a pci-e controller to handle the additional drives.

Also some sata ports might be shared with the PCI-E slots, refer to mobo, you may need to remove a PCI-E card for full access to all or some of the sata ports.

Haven't had the time yet to work on this. Hoping to get some time this coming weekend, doubtful though as the family and I are going to the Nederlands Friday and Saturday.

Just to give an update, I was referred to a thread on reddit (WD Easystore 8TB Compendium) that talked about this issue. Apparently, some of the white labels come with a SATA 3.3v pin and some power supplies are not compatible with it. My power supply was on the list of confirmed incompatibility. I followed the guide and used a small piece of kapton tape to cover the pin. Once covered, I plugged it back in and voila! the drive is now appearing and functioning well under both the BIOS and explorer.

Now my dilemma is deciding to keep Windows 7, use my upgrade to Windows 10, or install Linux Mint.