i have now win 7 ultimate with loader installed and i got legit pro key. can i change the key in ultimate so it will change to pro or need to reinstall ? thanks
1) No. 2) Yes. Plus, if the install media you have is an unmodified Ultimate version, you will have to modify it to enable the other versions locked on the DVD or use a new Pro version in order to install Pro.
I cannot remember who it was, but someone here managed to downgrade from ultimate to pro. He made a thread somewhere here last week.