Assume that you have the Lync Mac Meeting add-in enabled in Microsoft Outlook for Mac. When you click an online meeting link in Outlook, Safari or Firefox is started. Then, you click Join using Lync for Mac or Communicator for Mac, Skype for Business for Mac opens, and you receive the following error message:
You're not setup to join Skype for Business Meeting.
To fix this issue, install the November 2016 cumulative update 5.0.8308.974 for Microsoft Lync Server 2013, web components server.
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