I need help opening a port to play Counter Strike (original one). Here's what I try to do when opening a port: first I name it (Counter Strike Server) then I put in the trigger port 27015, for trigger type I put Both, for public port I put 27015, and for public type I put both and then apply the settings. But then when I make a dedicated server none of my friends can join it. Can someone tell me what I'm doing wrong?

ok you got the trigger right. and most people say u cant. im not sure but the public ports should be 27020-27039,1200,27000-27015