I am just wondering..

Why didn't you reinstall Poser using your legitimate serial number?

My Poser CD is hosed. It's scratched. But I paid money for it, and a lot of it, since I got it JUST as soon as Metacreations released it, and there's NO WAY I would buy it again just because I scratched my CD. So I installed a friend's copy and then used my legit serial number for it.

Anyhow, these flea markets are often full of warezed versions of software. If the copy you bought is not a legit looking Poser CD (orange and white cover, if iirc), that's exactly what you got: an illegal copy.