Parallels Dekstop 13.0.1 BE won't let me add a Physical Internal HDD to the VM system.
There is a SATA HardDrive in my system with a GPT partition table and a big (2TB) NTFS partition. I use it when normally booted in a Microsoft Windows installation located in another drive. The disk contains some user files and a few apps. There is no OS installed on it. The hard drive is recognized and works as expected under macOS too.
Please note: macOS (10.12.6) is installed on a third disk. I also cannot update: I had to downgrade because High Sierra breaks compatibility with some stuff I have and I don't like the
root login without password thingie.
My VM is actually a proper Windows 10 installation on an SSD which Parallels sees as Bootcamp and it works fine both natively and in the VM. In the VM settings though if I try to add a HDD it asks me what kind of drive I wish to attach. I can either create a new/use an existing virtual drive or use a "real" Hard Drive (Bootcamp). Problem is, only the SSD is seen as an available disk (the one with Windows installed on it) while my 2TB data disk does not appear.
I guess that is because it's not a Bootcamp/Windows hard drive, only a common disk with some files on it. I tried moving my pre-owned license and installing Paragon NTFS on this machine. Again, the Drive works as expected, I can view/move/edit/create/delete/rename files on it but Parallels still won't let me select the drive as an additional disk for my VM?
TL;DR and core question
What can I do to make my internal disk appear as a Bootcamp hard drive (preferably without actually installing Windows on it)?
Or, if impossible, how can I at least convince Parallels that my HDD is eligible for use as a VM drive?