Windows 8.1 Pro OEM CdKeys
This Product Cd Key could not be used for upgrading, you can use it to activate a fresh copy of windows (a clean installation of OS)
As we care about your time and money and want our customers to have a clear outlook, According to our investigation done for cheap Windows cd keys, somehow here is the clearest description among websites selling this product.
You can read about activation here:
>>> Ask Microsoft support that you want to activate the windows key.
2. After contacting MS Support, if you still can’t activate the windows cd key, Please Send us a ticket here.