How to deal with limited External Calling when using Lync server to make external calls

Posted on 2014-08-28
Last Modified: 2014-09-14
Limited External Calling when using Lync server to make external calls

Microsoft Lync Server, Cisco Firewall
One of my clients is running a Lync 2010 Server but recently he and others started to get this message which keeps popping up randomly every now and then. The message says:

Some calls to and from people outside of your corporate network may not connect due to a server connectivity problem. Try signing out and signing back. If the problem continues call your support team.

When the users hovers with his mouse over the Lync icon on the task bar it says: Limited External Calling.

The company has three Lync Servers 1- Edge 2- Mediation Server 3- Monitoring and Archiving.
All running Windows Server 2008.  

What are the things that I need to look for? Is it a Lync Server issue or does it have something with the firewall open/closed ports etc. The firewall is Cisco but I am not sure what make. How do I get that?  

Now my experience with Lync is very and I mean very limited if it ever exists so I will be extremely grateful if the answer is as simple and detailed please as it could be so I can fully understand and implement it.

Many Thanks
Question by:Mustafa Osman
    1 Comment
    LVL 23

    Accepted Solution

    The company has three Lync Servers 1- Edge 2- Mediation Server 3- Monitoring and Archiving.
    All running Windows Server 2008.  

    Here you said 3 servers and none of them are the Lync Front end? I think you're referring to Lync Front end as the Mediation server? normally Lync front end has the Mediation service in it collocated by default unless in a corporate size network you would install Lync pools with Lync Mediation server dedicated on a separate server.

    Anyways if you're referring to Lync PSTN calls then The message you posted "Limited External Calling" means that some services on Lync Front end or Edge didn't start or couldn't start. try check both servers for any Lync services that are not started and try start them or try restarting the Lync Mediation service and see if this works?

    If you're talking about a normal Lync-Lync call then try restarting Lync Front end service and see if that solves your problem and check if all Lync edge services are starting too.

    On Lync servers (FE and Edge) check for any Lync server related errors in the event viewer console. to open the Lync Event viewer console simply press Windows Button + R and type eventvwr then press enter and check for the Lync Server tab on the left pane.

    If there's any error with red mark there please post them here.

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