TCP Socket RST on the port TCP Port 3389

We are making the RDP Connection using TCP Tunneling on the port 3389 in C#.  But the TCP Socket is disconnecting in 50 seconds. 

4145    213.992742000   source(my pc)   destination (remote server) TPKT    71  Continuation
4146    213.998031000   source(my pc)   destination (remote server) TPKT    981 [TCP Retransmission] Continuation
4167    219.778181000   source(my pc)   destination (remote server) TPKT    85  Continuation
4191    224.575355000   source(my pc)   destination (remote server) TPKT    1354    [TCP Retransmission] Continuation
4246    238.663506000   source(my pc)   destination (remote server) TCP 54  49322 > ms-wbt-server [RST, ACK] Seq=173138 Ack=27613 Win=0 Len=0

In addition to that, I have gone through following the solutions provided. But it not worked for me.

RDP connections might fail due to a problem with KB2621440 – MS12-020:

Actually i have tried  this patch in the windows 7. But it already deployed in the machine.

Socket.Disconnect Method (Boolean): 

We are not disconnecting socket through code Explicitly. But the socket connection to the end machine (on the port 3389) is disconnecting internally after couple seconds. We have monitor this one using the wireshark. Eventhough, we have send the Keepalive packet in every 10 seconds, but its disconnecting the Socket after the 50 seconds. Due to this we are not able to send the datapacket to the end machine socket which is received from the  Tunneling.

Please help me to resolve the issue.

I have the gone the RD Gateway manager and Remote desktop services. Since I am testing the feature the in the corporate the network, I don't how to setup the RD Gateway Manager in the Windows 7 Machine. 

Please forgive me for grammatically mistakes

Thanks

Thangamani