Run Command Prompt
Type in "wmic path softwareLicensingService get OA3xOriginalProductKey"
Copy Key
Go to Settings > Update & Security > Activation
Select "Change Product Key"
Paste Key and Update
Run Command Prompt
Type in "wmic path softwareLicensingService get OA3xOriginalProductKey"
Copy Key
Go to Settings > Update & Security > Activation
Select "Change Product Key"
Paste Key and Update