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MTA-STS

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MTA-STS

SMTP MTA Strict Transport Security for inbound TLS policy.

Reading time:: 5 min
Difficulty:: Intermediate
Estimated duration:: 5 min
Prerequisites:: None
Last updated:: 2026-07-15
Author:: empire

Definition

SMTP MTA Strict Transport Security for inbound TLS policy.

TLS-RPTSMTP TLS Reporting for encrypted delivery failure reports.
AuthenticationIdentity signals for email: SPF, DKIM, DMARC, and related controls.

Invalid MTA-STS policyPublished MTA-STS policy is malformed or incomplete.
MTA-STS policy unreachablePolicy host or HTTPS policy document cannot be fetched.

Open step-by-step: Configure MTA-STS and TLS-RPTPublish MTA-STS policy and TLS reporting.

PreviousARC NextTLS-RPT

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