ImprovMX

4.2.1

ImprovMX deferred this after an anti-spam check. Retry later. Review content if the same deferral keeps landing.

5.7.1

ImprovMX rejected this as spam. Trim risky content and links, then resend a cleaner message.

5.7.1

ImprovMX blocked this for very low sending-domain reputation, often a DBL listing. Delist the domain, then retry.

5.7.1-2

ImprovMX blocked a mail loop back into itself. Fix the forwarding target so it does not point back at ImprovMX.

5.7.1-3

ImprovMX does not know this domain in its database. Confirm the alias domain is set up correctly.

5.7.1-4

ImprovMX has invalid forwarding data for this recipient domain. Fix the alias configuration in ImprovMX, then resend.

5.7.1-5

ImprovMX could not read the forwarding recipient. Fix the forward-to address in ImprovMX, then resend.