When trying to update a Windows 10 or 11 install to Pro, by going to Start > Settings > System > Activation > Change product key, and entering a valid Windows Pro edition product key, you may get the below error:
The product key you entered didn't work. Check the product key and try again, or enter a different one. (0x80070057)
To get around this, you will need to use a Windows Generic Key first to upgrade it to Pro