Hi All, I'm trying to configure the Kamailio Server (V 4.0.3) as Registrar with OverSIP server (V 1.4.1) as a Proxy for my WebRTC client; While calling UserB from UserA, the Kamailio is trying to find the UserB using address from Via address in UserB's REGISTER request; I'm also using GRUU and enabled the same in configuration file. Can someone help me what's wrong in my configuration / is Kamailio requires any additional settings to resolve this issue? Attached Files.zip contains the following files: OverSip-Kamailio.pcapng - Contains the packet capture between the OverSIP and Kamailio Servers. Kamailio-Logs.txt - Shows the error message that Kamailio is trying to resolve address and it's failed. User-records.txt - Output of "kamctl ul show". Kamailio.cfg - Configuration file for Kamailio. Note: I have configured MySQL as DBENGINE, but haven't created any DB tables. Thanks in Advance, Karthikeyan R DISCLAIMER: This email message and all attachments are confidential and may contain information that is Privileged, Confidential or exempt from disclosure under applicable law. If you are not the intended recipient, you are notified that any dissemination, distribution or copying of this email is strictly prohibited. If you have received this email in error, please notify us immediately by return email to mailadmin(a)spanservices.com and destroy the original message. Opinions, conclusions and other information in this message that do not relate to the official of SPAN, shall be understood to be nether given nor endorsed by SPAN.