To ensure a fully trusted authentication via HTTPS, you can request and import a certificate delivered by a Certification Authority (CA-signed certificate).
When you import the certificate you need to:
Import the root certificate
Import the intermediate certificate
Import the CA-signed certificate
Check and import the root certificate
Complete all procedures to successfully import the certificate.
The certificate is now installed on the server.
Check and import (if needed) the CA Root certificate also into the workstations web browser. That will secure the complete data workflow between the workstations and the server.