Hello, sincere apologies if you know the answer was somewhere in the forum - I just wanted to be really sure that I am doing the right thing. Firstly I'm obsessed with the legal part - I want to leave the shady business behind and have only non-pirated versions on our computers, secondly (tbh, that's kind of motivation for the first part) the anti-piracy dept of Microsoft is intimidating and the last I would want is to see the program I bought from the shop to start showing me the black desktop and terrorise in other ways. So my case is as follows: I will update the OP on my computer to Win7 Ultimate. Can I simply reinstall the Win7 Home Premium on my brother's computer? Or should I still do the install using the same name that was already once used when installing with that product number? Or lastly (which I don't really want to do because I want my computer to be cooler and edgier than my brothers, lol) - should I simply use the upgrade on his computer and simply not mess with my Win 7 Home Prem? Thanks a lot if you find a minute to analyse my situation and give some good advice!