I know you guys must be thinking why not use ultimate if you could? Well, my system is already licensed for windows 7 professional, however it is not out yet and I want to use it now. So I've got the msdn version of w7 professional Can you use the same cert and key as posted in the w7 repository? slmgr -ipk 22TKD_F8XX6_YG69F_9M66D_PMJBM If not, it would be helpful if someone could post keys for various flavors of windows 7 (Home Premium, Professional, Ultimate, Enterprise) That'll be greatly appreciated. Thanks in advance.