Our Microsoft 365 licensing is a Windows 10 Enterprise upgrade license. In order for the upgrade license to activate fully, it requires a Windows 7, 8 or 10 Pro or higher base license. Windows 7 Pro systems often have the license key on a sticker on the computer case. Windows 8 and newer computers do not have this type of sticker. To retrieve the license key, open a Windows Powershell window as an administrator and enter the following command.
(Get-WmiObject -query ‘select * from SoftwareLicensingService’).OA3xOriginalProductKey
This will display the original product key. Copy this key.
Right-click on the Windows start button and select System.
Select Change product key or upgrade your edition of Windows.
Enter the product key to activate the base license.