In your Login keychain, delete all e-mail address certificates.Delete all keychains starting with OC_Ke圜ontainer.

Open Keychain Access from /Applications/ Utilities folder.Go to Finder > press Command+Shift+G > type in /users//documents > navigate to Microsoft User Data > delete the following folders: Microsoft Lync Data and Microsoft Lync History.Logs > Microsoft-Lync-x.log and Microsoft-Lync.log.Keychains > all files beginning with OC_Ke圜ontainer.Go to Finder > press Command+Shift+G > type in /users//library > delete the following files:.Clear DNS cache: in Command Prompt run ipconfig / flushdns command.Navigate to Users > username > AppData > Local > Microsoft > Office > x.0 (x.0 corresponds to the Skype for Business/Lync version: 16.0 = Skype for Business 2016, 15.0 = Skype for Business 2013, 14.0 = Lync 2010) > Lync.Delete any sign-in info ( only in Skype For Business 2013/2016).Skype for Business 2016 for MAC Skype for Business/Lync for Windows Your Outlook and Lync integration is not functioning properly.Common reasons you will want to clear Lync cache include: Skype for Business/Lync caches files locally on a PC or MAC to pull information quickly and efficiently.

Uninstall skype for business update