notsecure verified
Not secure
Messages refused by our own TLS requirement, not by the receiver.
In detail
A message counted here was stopped because the throttle profile demanded encryption the receiver did not offer. It is a policy failure rather than a delivery failure, and the fix is a decision: either the destination is worth relaxing security for, or those messages should not be sent. Non-zero values are worth surfacing loudly, because nothing else in the interface explains why mail to a particular destination simply stops.