Looking for logging into the Lync Sign In Process site and are not getting the correct working link for it? In such a case, you can use the links given here by searching your desired login page in the search box. If the page is present on our website then you will get all the links related to the Lync Sign In Process site. After that you can login as usual with your login credentials.
https://blogs.technet.microsoft.com/praj/2016/10/14/skype-for-business-client-sign-in-call-flow-detailed/
https://blogs.technet.microsoft.com/nexthop/2018/04/09/sfb-online-client-sign-in-and-authentication-deep-dive-part-1/
https://channel9.msdn.com/Events/Lync-Conference/Lync-Conference-2014/CLNT400-R
http://www.google.com.tw/url?url=http://video.ch9.ms/sessions/lync/2014/CLNT400_Ricks.pptx
http://www.google.com.tw/url?url=http://blog.schertz.name/2012/12/lync-2013-client-autodiscover/
https://www.youtube.com/watch%3Fv%3DI1ZrP_PykB8
http://www.google.com.tw/url?url=http://blog.51cto.com/jasoncheng/1350096
https://support.office.com/en-us/article/sign-in-to-and-sign-out-of-lync-b443c994-48bf-441c-9e33-ba7c804beb18
https://uctejas.wordpress.com/2016/06/30/lync-client-sign-in-process/
https://techmikal.com/2014/02/17/lync-authentication-process/
https://www.dell.com/support/article/us/en/04/sln163442/lync-2010-and-2013-client-login-troubleshooting-for-servers
https://abdelrahmanpro.wordpress.com/2017/05/27/sfb-lync-mobile-sign-in-overview/
http://www.google.com.tw/url?url=http://communicationsknowledge.blogspot.com/2013/01/lync-communicator-login-process.html