My friend and I have downloaded Trine 2 and Trine 3. We are both able to join someone else's game independently, and others can join each of our game, but we can not join each others game. We have opened the ports on the routers, allowed passage for both windows and anti virus firewalls. He has ensured that steam will permit access as well. We would like to start this game together any suggestions on how we go about achieving this.

Error Code is 262147....sorry dyslexic

Tonight have done an %app...txt edit and a clean boot without success. Can still join others games but not my friends.