I am having an issue downgrading to 7 Ultimae to 7 Home premium. I am doing it because my brother had his computer worked on by our Nephew, and he went from XP to 7 ultimate with a hacked copy of 7 ultimate. I have done a fresh install, but it keeps starting and reverting back to Ultimate, The kicker os that I can go to KEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion and see windows 7 home premium as the operating system with no CD product ID. I'll add the product key, and go to regiser it but it won't let me activate it. The thing I have an issue with is that even after a fresh install, it starts up and says windows 7 ultimate. What am I doing wrong??