OS: Windows 8 HDD: 4TB WD Green plugged in to a Seagate FreeAgent GoFlex Desk PC: Awesome home rig to Acer Aspire U all-in-one.
So this is a pretty weird problem. The drive worked perfectly fine on my home rig. Using this goflex desk thing, my 500GB NTFS and other identical 4TB drive (empty and NTFS) opens up in Windows Explorer no problem.
Diagnostics, diskcheck, disk management, etc. All show that the drive is online and healthy, but all options to tamper with the drive in any way or greyed out in disk management, and a volume doesn't show up for the drive in diskcheck.