Assume that you set the automatic logon through Windows Credentials for Microsoft Skype for Business 2016 on a non–domain-joined computer. (You can access the Credential Manager item in Control Panel.) When you log on to the client that has December 8, 2015, security update installed, you are prompted for credentials.
Resolution
To resolve this issue, install the February 9, 2016 update (KB3114696) for Skype for Business 2016.