Help me please

Guys, When I add a server with 7777 port, it says (Retrieving Info) 'IP Address'.
But, I can join a server that not using 7777 port. Can you help me to fix it guys?

REP+ to people who help me (If success).

EDIT:
Also, if I add a server with 7777 port in my friend's pc, that server is on and I can play in it.
But, my friend don't know how to fix this too.
Sorry for my bad English.