Unfortunately, we're developing for UWP only, which isn't backwards compatible with other Windows operating systems. We have a little more information about this here: Adobe XD Windows Update | Creative Cloud blog by Adobe
Hopefully, you'll be able to encourage your IT department to consider upgrading.
That link is exactly the information I was trying to find.
My organization is in the tens of thousands, so I don't think I have much sway over IT's decisions. I would have to check, but perhaps we can ask for our machines to be upgraded individually. It's hard to justify an upgrade like that just to test a tool we may or may not end up using, though.
I'll try to test on a personal machine, for a start.
Thanks for your help!
Glad you found the link useful, and good luck!