I have read many posts stating that the current MSDN and Partner MAK keys are not working with 8.1 Pro/Ent. I stupidly upgraded my laptop anyway and am now stuck with an inactive installation. It isn't the end of the world but I was wondering what the hold up is with legitimate MAK keys not activating if anyone knows for sure. Is it the fact that 81 uses a new authentication process (v6) or has MS not turned on the key compatibility with their servers. Since I am trying to activate our MAK keys to test some of our software I am not using a KMS server. Thanks for whatever you can tell me.