Originally Posted by
gpobernardo If you've upgraded from a genuine copy of Windows, a product key will automatically be generated for Windows 10 during the upgrade. You may try using the official product key that came with your Operating System and laptop. With this, there is no other legal way of obtaining a product key.
The key that came with his system has zero chance of working, because it is NOT a W10 key. It's impossible to activate W10 with anything but a W10 key.
We must also be very specific about what is meant by "upgrade". A clean-install, as applied by the OP, is also an upgrade. What you are describing is only true of an in-place upgrade however!