Symptoms
Assume that you run Microsoft Skype for Business 2015 (Microsoft Lync 2013) on an Always On/Always Connected (AOAC) device, such as a Microsoft Surface Pro or Microsoft Surface Book laptop. When you close the lid of the laptop, or when the system is in suspend state, Skype for Business 2015 (Lync 2013) does not sign out.
Resolution
To fix this issue, install the April 4, 2017, update (KB3178731) for Skype for Business 2015 (Lync 2013).
Note Lync 2013 was upgraded to Skype for Business in April 2015.
