What to Do if the Active Directory Connector Fails to Contact Active Directory Over SSL?

If the Active Directory Connector fails to contact Active Directory over SSL and the following error message displays, restart the AD domain controller.

Failed to open connection to
ldaps://server.example.com:636,
error(91): Cannot connect to the LDAP server,
reason: SSL_ForceHandshake failed: (-5938)
Encountered end of file.