1. To Change Product Key Number in a Command Prompt Open an elevated command prompt. In the elevated command prompt, type in the command below and press enter.
NOTE: Substitute XXXXX-XXXXX-XXXXX-XXXXX-XXXXX in this command below with your actual product key number with dashes instead.
slmgr.vbs /ipk XXXXX-XXXXX-XXXXX-XXXXX-XXXXX
2. Type slui.exe 4 to access the phone activation screen and follow the steps to activate over the phone.