Re: License violation
"If he had Vista Business from work, it was licensed to his employer, not to him personally. Therefore, he's not allowed to buy just an upgrade."
Unless it was a licence-tied-to-the-machine-and-sticker-stuck-on-the-side-of-the-box scenario.
"In fact, he shouldn't be using even Vista at home."
Well, I think we can all agree on that, but isn't the "at home" redundant? [Troll icon for this...]