After having bought my computer used from a repair shop a little more than a year and a half ago with all the software already installed, I suddenly am having issues with Microsoft professional plus 2010, saying that it's unregistered and asking for the activation code. I bought it used, of course I don't have it. I finally got to talk to a live person from probably India today, and he told me since it was pre-installed when I got it I'd have to contact Dell (I doubt that Dell installed the software, probably the previous owner did). After reading around on this forum, I'm finding this seems to be happening a lot!
Is it possible for a hacker to swipe an existing code, then render it unusable?

And also, I refuse to upgrade my OS to windows 10, not just because my son hates it, but because MS is pushing so hard I can't trust it. Do I need to just let go and go with Apple come spring? I'm not buying a new copy of office just to keep it running on a computer that I expect to break down soon.