Consider the following scenario:
You are in a call in Microsoft Lync 2013.
To perform a consultation, you open a new Lync window by entering a new public switched telephone network (PSTN) number or a user name.
Note The first call is automatically put on hold when the new call is answered.
After you finish the consultation, you go back the first call.
You transfer the call to the PSTN number or to the Lync user by hovering over the Call button.
In this scenario, the Current Conversations option is not displayed on the Transfer Call tab when the Call button is displayed.
To fix this issue, install the November 10, 2015, security update (KB3101496) for Lync 2013 (Skype for Business).
Note Lync 2013 was upgraded to Skype for Business in April 2015.