You must select Authentication Agent in the Chains list of Mac Client to initiate the authentication process on Windows computer where the Authentication Agent is installed. To enable the Authentication Agent chain in the Mac Client, perform the following steps:
Navigate to /Library/Security/SecurityAgentPlugins/aucore_login.bundle/Contents/etc/ and open aucore_login.conf file.
If the configuration file does not exist, create a new file.
Specify verifyServerCertificate=true in the configuration file.
Click Save.
Restart your computer.