This seems to have produced something that looks an awful lot like a product key. Thanks!

Where am I supposed to get the key then? I just bought the laptop and it had windows on it. There is no key on the back or anything.

Just to be sure I understood correctly - if I get a matching...

I have a laptop that originally had windows 8 on it. In its long life the drive got formatted many times, many different OSs were installed on it and now I even have a completely different drive....