Winuser said: View Post
There was no other option listed to continue without a key. There was only the box to insert the key, the option to cancel and the option to continue which was grayed out.
cereberus said: View Post
Are you sure you are trying to upgrade using correct edition eg Home normal, Home SL, or Home N?
That's a distinct possibility, there should normally be a 'I don't have a product key' option (albeit in the small print at the bottom).

Clean Install Windows 10