I wanted to downgrade my laptop back to Windows 8 because Win10 does not work that way. So far no problem, but I would like to know if the key is then taken over. Yes, I know that a Win8.1 key costs 8 euro, but you save where you can. So, does anyone know?
A Windows 10 key is not valid for Windows 8.
A Windows 8 key but for Windows10.
Ah ok.
Download Ubuntu that is a Linux system but has a downgrade tool