The dedicated connection is not going through a router, so you do not need to forward it; ALL ports will be connected to the server.
Thank you very much for the reply.
you are right. the issue was some thing else. anyway it is solved.
but now I have another issue, some of the other computers in the LAN also need to access the server, but they fail to access it.
if I disconnect the LAN card in the server and reconnect it, while internet is connected, then the other nodes are able to connect.
what could be wrong?.