Dear All, On Linux, one usually acquires PJSIP from its distro's packaging system. When a distro decides to turn on IPv6 functionality when compiles PJSIP it will be active for all its users. However, IPv6 can be disabled on per-user basis on kernel level (append „ipv6.disable=1” to kernel parameters). Disabling this service is possible on Windows, too. When PJSIP DNS resolver is in use with PJ_HAS_IPV6=1 defined at compile time but IPv6 is disabled on the user machine, init_sock() fails at pjlib- util/resolver.c:310 (with errno 97 (or 120097 in your case): "Address family not supported by protocol”). The problem is that the previous IPv4 socket creation was successful, the user could go on with only that service, however, the whole function fails because of this. Best regards, Ákos _______________________________________________ Visit our blog: http://blog.pjsip.org pjsip mailing list pjsip@xxxxxxxxxxxxxxx http://lists.pjsip.org/mailman/listinfo/pjsip_lists.pjsip.org