I have problems when connecting to a livemeeting created by a partner when I'm at our company . The authentification type is set to anonymous. I'm able to connect when I'm at home outside our company. I spoke with our partner and their access edge is configured to listen on port 443. I'm able to connect to other sites at the partner on port 443 using a browser.
When I look in the eventlog on the client I see that it tries to find the SRV record of the access edge (which is present) and then it fails back to use the sipexternal values.
What about the RTP ports (50000 to 59999)? Are they being blocked by any firewall on the path? While your at it check 5061 as well because based on your config, witch i don't know what it is, it might have to be open as well.
Is this a federated partner? IT might have something to do with the DNS A record resolution for the partner's Web Conferencing Edge FQDN operating differently when inside your network than outside.Jeff Schertz, PointBridge | MVP | MCITP: Enterprise Messaging | MCTS: OCS