Hi... All , I have Configured OpenSER 1.3.2-tls source code & compiled successfully . Registration is successful with TLS handshake . Below is the scenario of my test . UA1 & UA2 clients Registers on TLS. When UA1 send INVITE request to UA2 I got the Following Error : : SIP/2.0 477 Send failed (477/TM) When i scanned through the logs of openser I got the following Message : proxy always trying to establish TCP connection but it Fails. Jul 11 23:55:20 [22415] DBG:core:check_via_address: params 10.200.68.220, 10.200.68.220, 0 Jul 11 23:55:20 [22415] DBG:core:tcp_send: no open tcp connection found, opening new one Jul 11 23:55:20 [22415] ERROR:core:tcp_blocking_connect: poll error: flags 18 Jul 11 23:55:20 [22415] ERROR:core:tcp_blocking_connect: failed to retrieve SO_ERROR (111) Connection refused Jul 11 23:55:20 [22415] ERROR:core:tcpconn_connect: tcp_blocking_connect failed Jul 11 23:55:20 [22415] ERROR:core:tcp_send: connect failed Jul 11 23:55:20 [22415] ERROR:tm:msg_send: tcp_send failed Jul 11 23:55:20 [22415] ERROR:tm:t_forward_nonack: sending request failed Jul 11 23:55:20 [22415] DBG:tm:t_relay_to: t_forward_nonack returned error Jul 11 23:55:20 [22415] DBG:core:parse_headers: flags=ffffffffffffffff Jul 11 23:55:20 [22415] DBG:core:check_via_address: params 10.200.68.220, 10.200.68.220, 0 Jul 11 23:55:20 [22415] DBG:tm:run_trans_callbacks: trans=0xb5db7e50, callback type 128, id 0 entered ACC: call missed: timestamp=1215800720;method=INVITE;from_tag=20282693445eido3yklvo4;to_ta g=;call_id=8307080595eido3erlzgw;code=477;reason=Request Failure - Presently i don't have any DNS server , is that really matters ?? - While openser tries to open TCP connection with UAS it's sending port ' 0 ' , but fails is it ok .?? , or Anything I'm missing in Configuration . I have Attahced config file Also. Thanks & Regards, Pravin.swami Please do not print this email unless it is absolutely necessary. The information contained in this electronic message and any attachments to this message are intended for the exclusive use of the addressee(s) and may contain proprietary, confidential or privileged information. If you are not the intended recipient, you should not disseminate, distribute or copy this e-mail. Please notify the sender immediately and destroy all copies of this message and any attachments. WARNING: Computer viruses can be transmitted via email. The recipient should check this email and any attachments for the presence of viruses. The company accepts no liability for any damage caused by any virus transmitted by this email. www.wipro.com