Consider the following scenario in a Microsoft Lync Server 2013 environment:
You're using an Apple iPhone or Apple iPad that's running Apple iOS 10.0.
You have Microsoft Skype for Business 2015, Lync 2013, or Lync 2010 installed on the device.
You try to join a meeting from outside the Skype for Business or Lync app. For example, you tap the Join Meeting link in an email message or calendar appointment in an app other than Skype for Business or Lync.
In this scenario, the device tries to start the desktop version of the website instead of the mobile version. The desktop version won't try to start the app. Therefore, you can't join the meeting.
Note The mobile version would try to start the Skype for Business or Lync app and join the meeting, or redirect you to the app store if it can't join the meeting.
To fix this issue, install the November 2016 cumulative update 5.0.8308.974 for Lync Server 2013, web components server.
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