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generic error

DMARC Fail — Authentication Did Not Align

Neither the SPF-authenticated identity nor the DKIM-authenticated identity supplied a passing path aligned with the visible From domain.

Diagnose your exact bounce DMARC Alignment Lab

Most common causes

  • SPF passes on a third-party envelope domain but is not aligned
  • DKIM signs with a provider domain rather than the visible From domain
  • The relevant authentication mechanism failed
  • Strict alignment is enabled without exact-domain identities

What to verify next

  1. Run DMARC Alignment Lab
  2. Inspect Authentication-Results in the message header
  3. Verify custom bounce and DKIM domains
  4. Inventory every legitimate sending platform

Best diagnostic path

Live analysis

Mail Failure Doctor

Classify the complete rejection and preserve provider-specific diagnostic context.

Open analysis → Live analysis

DMARC Alignment Lab

Compare visible From, envelope sender and DKIM identities without reducing the result to a pass/fail label.

Open analysis → Live analysis

Email Infrastructure Digital Twin

Map the domain’s public mail infrastructure and provider relationships before remediation.

Open analysis →

Why the exact message matters

The same status family can be triggered by different conditions, and providers frequently add diagnostic text that narrows the issue. Use the complete rejection text rather than treating the numeric code as a complete diagnosis.