The license key becomes invalid following the 10 update.
The license key becomes invalid following the 10 update.
It's attached to a label on his case. (He got a custom-built PC)
He got Windows 10 from Microsoft's site without the installer, which is really problematic!
Tell him to try another computer if needed, and get the program from the link provided. He’ll need a USB drive or blank DVD, though it should work with his Windows 8.1 OEM key.
You can press the shift key while clicking restart in Windows, then use the troubleshooting options to go back to an earlier version. This usually resolves the issue.