So I have an old PC with a Windows 10 installation. I upgraded to Windows 10 from a Windows 8 Retail which I still have key and dvd-rom for. I am thinking that I format the old PC and use my old Windows 8 DVD to install on the new PC and then upgrade that one to Windows 10. Is this possible? Legal? Or could I even create a USB stick with the Windows 10 Media Creation Tool, install that one on my new PC and activate it using my Windows 8 Key? Microsoft support is pretty much impossible to get a hold of. Like always.
As long as you have only one computer using the key (including upgrades), then you\’re fine and you should be able to do exactly what you want to do.