When you start Microsoft Skype for Business 2015 (Lync 2013), MAPI connection to Exchange Server may not be available to the client.
Additionally, you receive the following error message:
Your Outlook profile is not configured correctly. Contact your support team with this information.;MAPI unavailable
To fix this issue, install the August 1, 2017, update (KB4011046) for Skype for Business 2015 (Lync 2013).
Note Lync 2013 was upgraded to Skype for Business in April 2015.