Router Help! >.<

I am using a Linksys router and I cannot seem to play online with my brother using a computer next to mine. We are on the same router, however, everytime he joins a game online and I try to join it, it wont let me. It says "[OMFG] Your Name Suckrz" and it disconnects me.

I don't know if this is a port problem, if so, can someone tell me the ports to ESF? That would be most appreciative.

/atticus

Port 27015

You should also know you can't play with him if he is using the same cd-key as you.

u guys can do a LAN game where you play against each other if you use WON =o if you have the original half life game, install it in both of your computers and dont use steam. make sure update half life to 1.1.1.0 thoe