Hi all. 1.Registered U.E with IMS network. 2.After 5 seconds .Un-register(ru) the U.E. 3.Try to re-register(rr).PJSIP is trying to send packets via UDP protocol.It appears in log but packet is not sent out to IMS network.Did any one observed it ? 4.After few sec re-register is sent using TCP protocol.But getting a 403 response. Any one faced this issue? Any suggestion/insights to solve the 403 error . Thanks P.S.Manika Vasagam