I can't get The Norton firewall to allow Vent to connect

At the moment i am at my friends house and i would like for him to join vent but i tried to get the Norton firewall to allow it. i tried to play with all trusted apps. put vent as a trusted program but all it says on vent. "Contacting Server" i know its my friends firewall just need to know how to be able to get it to trust vent. anyone know how to use Norton firewall

P.S i wanna join the clan metting explain school stuff etc. sense now i have know almost everyone