I have Ubuntu 20.04 installed on my laptop. I want to go back to Windows 8.1, but it doesn't work. When I put in my install USB it doesn't work. It says "Insert proper boot device". I checked the Windows installation USB on an another PC and it worked there.


So you want to reinstall Windows.

Check your firmware (BIOS) for this: Did you (re)enable Secure boot? Did you (re)enable UEFI boot? Is the installation media UEFI bootable?

Windows 8.1 requires all these things or it will not install.

| improve this answer | |

Not the answer you're looking for? Browse other questions tagged or ask your own question.