Hi all, was looking for a little help as i'm at wits end. I'm trying to downgrade my parents laptop from Windows 8 to Windows 7 Ultimate. I ran into the issue with the whole locked OEM partition, i tried using killdisk but not sure i used it correctly (this may solve my problem) The laptop is an HP pavillion. I tried erasing just about i could see on the list, am i supposed to wipe the C drive and reinstall windows clean? Any help would be greatly appreciated! And more infos if needed!