SfBO / Lync Server 2013 / SfB Server 2015 requirements Outlook Mac build 15.27 (161010) required for Outlook integration.Skype for Business Server 2015 or Lync Server 2013 or Online.For updates you can use Microsoft AutoUpdate or download and install manually from the above URL.So great to see the Mac client being invested in and updated for fixes and new features. I noticed on tech community there was an update for the Skype for Business Mac client released yesterday on 5th October.