Activation de Windows

 There is a faster and easier way to upgrade to Windows 10 Pro if you have the product key for Windows 10 Pro For Refurbished and your Windows was activated as Windows 10 Home.

Go to Start > Options > Update & security > Activate > Change Product Key
Use the default Windows 10 Pro key.
VK7JG-NPHTM-C97JM-9MPGT-3V66T

This key is used from Windows 10 Pro when installing. It will not activate.

The Windows will upgrade to pro and request a restart.
After the restart open an Command Promed with Administrators privilege and execute the commands bellow.
slmgr /upk

This will remove the previous Product Key

slmgr /ipk XXXX-XXXX-XXXX-XXXX-XXXX

This will install your product key. Where XXXX is your product key located in the sticker of WINDOWS 10 PRO FOR REFURB PCS