Now, in the Keychain Access application, navigate to System under Key chains and select Certificates under Category on the left pane.You will be asked to insert your password again, insert it and click “Update Settings”.Then click “Always Trust” on the popup window.
The Keychain Access Insert your password and click “Modify Keychain”. The following message will popup, change the Keychain to “System” and click ‘Add’. The following guide was written by a colleague of mine, Lior Gilboa and it explain how to install a root CA certificate on a MAC client: Those root CA certificates are required in order to sign-in into Lync rather it’s on the internal or external network. Recently we got some support request tickets regarding MAC clients which weren’t able to sign-in into Lync because they were missing the necessary root CA certificates.
