www.nsoft-s.com

I face an problem which is similar to https://www.experts-exchange.com/questi ... error.html

Log shows:
[LOGIN] Login data: , nick: Lee, auth_type: 0
[28.11.2019.19.38.56] [LOGIN] user logged in
[28.11.2019.19.38.58] [INFO] PING
[28.11.2019.19.39.28] [INFO] PING
[28.11.2019.19.39.58] [INFO] PING
[28.11.2019.19.40.28] [INFO] PING
[28.11.2019.19.40.58] [INFO] PING
[28.11.2019.19.41.28] [INFO] PING
[28.11.2019.19.41.58] [INFO] PING
[28.11.2019.19.42.28] [INFO] PING
[28.11.2019.19.42.58] [INFO] PING
[28.11.2019.19.43.06] com.nss.mychat.SocketConnection.MyChat$connection: 305 Socket is closed

I even check for my firewall. There is no problem on server and pc.

Can you make a screenshot of your Windows Defender Firewall window with MyChat Server in it?

I make sure TCP 2004 was opened for connecting my chat messenger .

Ок, please check connection to server from another computer in your LAN by MyChat Client for Windows.