Summary: I purchased this BECAUSE it advertised Windows 7 as the OS. When I turned it on... Behold, Windows 8.1!!! I haven't used Windows 8.1 yet and am not upset with that program, I'm annoyed because I didn't receive what I paid for. I'm debating on returning it because it was advertised incorrectly. Now of course the current add says "Windows 8.1" as the OS. Hmmm, the OS changed without my consent/knowledge, what else changed?