Connections Issue

[Marlin]

Hello i just started my l2 server and i am able to connect on other computers but my friend cant get in. He is able to connect to login server but at server select the ping is 9999 and he cant get in? anyone know why

[FighterBoss]

you opened ports?you closed down the firewall?

you wrote at internalip and on gameserverhostname your no-ip?

[DominiQue]

Are you sure that u wrote the ip correctly ?

Or u have a gs debug ?

[josecarlosfl18]

What core are you using??? I know that GF, EP and Freya has some little trick on ip configs...