Issue
How to confirm ServiceNow email servers are using Opportunistic TLS
Release
All versions
Resolution
From external network we can confirm that ServiceNow email servers are accepting TLS connection by sending ehlo message to one of our inbound MX records.
Alternately, go to public websites as below and enter the domain i.e. service-now.com to check the same:
https://luxsci.com/smtp-tls-checker (This is a third-party page, not sponsored or supported by ServiceNow.)