Originally Posted by Squeek
If I'm understanding it right, your legitimately purchased copy could stop working if your CD key, somehow, became public knowledge. It would be forever banned.
Once I hired a kid to work for me who turned out to be quite an adept and active hacker. After about a week, I noticed that my Windows installation disk was missing, and I asked him about it. He said he had "borrowed" it.
I got the CD back but always wondered if he'd uploaded a copy of it somewhere and how many "pirates" were running my copy of Windows on their machines. If Microsoft were using this kind of copy protection then, I probably would have been forced to go out and purchase another copy.