Attempts to install the BCCA (Auth Connector) fail even though the server's certificate store shows an Entrust certificate installed.
Entrust Certification Authority (2048) is a prerequisite for the installation of the Auth Connector, see document: Deploy the Auth Connector.
Confirm that the Entrust 2048 certificate is the Entrust certificate installed. There are several different versions of Entrust certs, the certificate that the installation is looking for is Entrust Certification Authority (2048).
Download the Entrust CA (2048) root certificate from Entrust.net