OK, I don't know if this is the right sub-forum to post in, however I couldn't find any better.

An online "friend" of mine is so keen on starting his own HYIP - however, he's only 15 years old.
I've told him a story or two about HYIPs/Autosurfs which has failed hard (12DailyPro, etc.) where the owners has been sued, and maybe even ended up in jail.
However, this "friend" of mine doens't seem to care about him or his parents going to jail or getting huge fines for his own actions, just for the hunger of quick cash.

Nothing I tell this kid sticks onto his brain, and even after weeks of discussion with him he still wants to open that HYIP, dealing with thousands of dollars which doesn't belong to him, and he doesn't care about the consequenses either.

Now, I don't want him to end up in some financial crisis as it won't only affect him, but also his parents if he has to take up loans or similar, and all his users which will probably lose their cash if he manages to f* up..
I need you guys now, and I need your help.
What should I tell his to convince him not to start an HYIP?

It seems to me you've done everything anyone could expect of you. He clearly isn't in to taking advice, so maybe you just have to let him find out the hard way.

Well, I have to agree with Realist that you have done everything you are supposed to do. While there is nothing to lose, why don't you try another approach? Ask him what he plans with his investors' money. Where will he invests it, how did he plan to pay the investors? If he want to start a HYIP, he has to take it seriously and plans everything the best he can.