The process is next:
When you start the client, it's gonna connect to 55999 which is MHP server, then it's going to 44405 which is the Connect Server.
If the GameServer and Connect Server are online, you will see the server name button. (Connect Server is telling the client that Connect Server found the GS online and you can connect to that server name). After you click the server name button, you are in the login screen and you are now connected to the GS and disconnected in the ConnectServer because you successfully connected to GS.
So if you are seeing the server name button, but it's disconnecting you when you press it to get into the login screen, there are a few things to check:
- Client is not connecting to the correct GS port (ServerList.dat file, also check MapServerInfo)
- Port is not opened (Port forwarding, firewall port allow)
- Make sure you checked every thing in the configs regarding changing 55901 to a randomly preferred port.