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I am working on troubleshooting a Lync 2010 deployment and have hit a snag. I have just about everything working except for the external meeting piece and don't really know where to look.

Environment is as follows:

  • 1 Edge server (av, webconf, sip)
  • 2 Directors
  • 2 Front Ends
  • 1 ISA (reverse proxy for address book, dialin, meetings)

I receive the following error when attempting to join an online meeting outside of the internal network with Chrome as both a guest and as an authenticated user. Sometimes it hangs, sometimes it fails right away, but it always fails eventually. I can join and run meetings between clients on the same domain but outside of that (internet), I keep getting this error.

enter image description here

I have double checked all client side settings through LCP. Another interesting symptom I’ve noticed, not sure if it is related but when joining the meeting via IE and choosing audio/video the client will connect briefly and then immediately disconnect even with devices that have mics and webcams.

So at this point the external users are only able to join using IM only but are not able to use any of the sharing features, screen viewing, etc.

enter image description here

I was able to capture the following screen shot, but cannot reproduce the issue. I am hoping this gives some clues, my googling has led me to believe that this error is unrelated to my others as this one seems to refer to mic/webcam problems.

enter image description here

Where should I begin looking in order to troubleshoot and hopefully solve this issue? I would be happy to provide more details if I have missed anything here. Your help is much appreciated, thank you.

share|improve this question
could be a firewall issue. Lync uses a number of ports in addition to https. Including UDP/3478, RTP/TCP 50,000-59,999 – Dmitri Chubarov May 26 '12 at 2:19
I have checked the firewall ports, but I can double check to be sure. – jmreicha May 27 '12 at 8:37
Any eventlogs? Dropped/Denied packets on the firewall? Can you do conferences using the Lync client from the outside? – MichelZ May 28 '12 at 10:03
What event log events should I look at? The network guy said he isn't seeing any drops but I can look more thoroughly to be sure. I have the Lync client working from external networks so I believe conferencing works but I will have to test that as I'm not 100% sure. – jmreicha May 29 '12 at 0:24

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