When you install Poser 5, you put in a challenge code, and CL gives you a response code, you need both to get poser to work. You have to contact CL by WEB, PHONE, etc to get the response code. (see install/register in the manual) Somebody said it was simular to MS XP Windows registeration. They also mention this was tried in Propack, but they got a lot of complaints, and discontuied it.