This is, as far as I can tell, a 2012 model. OEM Windows 7.
So if you want Windows, and the W7 code sticker is readable, you can always take the drive down to bare metal, set the EFI to legacy mode, install Windows first, then MX alongside (dual boot).The simplest fix was to wipe the drive, and ONLY install MX-17. That's what I did.
I really wonder if I should have installed everything legacy INSTEAD of UEFI...
Legal W7 ISOs aren't hard to find. (I could even set up a download.) Getting all the updating done used to be a nightmare, but WSUS Offline is a godsend. Still takes time, but you don't have to babysit it.