Delegate can't transfer a call in Lync 2013 UI if you have June or July update installed - Microsoft Support [MS]

Delegate can't transfer a call in Lync 2013 UI if you have June or July update installed

Lync Server 2013 Skype for Business More...Less

This issue only occurs when you use Microsoft Lync 2013 that has the June update or July update installed. When you receive a call as a delegate and select the work number to transfer the call to another user, nothing happens in Lync 2013 user interface (UI), and the call can't be transferred.

Resolution

To fix this issue, install the October 13, 2015 update (KB3085581) for Lync 2013 (Skype for Business).

Note Lync 2013 was upgraded to Skype for Business in April 2015.