How to enforce TLS negotiation for any SMTP traffic?


as from here I can configure "Require sender email domains" to enforce TLS negotiation (whitelisting). Beside this I can configure "Skip TLS negotiation" (blacklisting).

For compliance and legal reason I need to configure TLS negotiation as default for any domain. How would that be possible?

Edited TAGs
[edited by: Erick Jan at 9:52 AM (GMT -8) on 12 Feb 2024]