and use your Windows 7 OEM key to install Windows 10, and activation should succeed. Do note that this will work only once. Once you’ve used your free upgrade, that Windows key is once again ...

If you activated Windows 10 by upgrading from a valid Windows 7 or 8 installation or with the ... If you purchased a device with an OEM key, such as a Dell or Lenovo laptop, the Windows 10 product ...