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Gmail 550 5.7.1 — Policy Rejection

Gmail rejected the message because the sender, recipient or message did not satisfy a policy applied to the delivery.

Diagnose your exact bounce Email Infrastructure Digital Twin

Most common causes

  • Destination or sender policy does not accept the message
  • Authentication or reputation evidence is insufficient for the policy path
  • The message is being rejected by a domain-specific rule
  • The detailed text following the status code identifies a more specific cause

What to verify next

  1. Use the complete provider diagnostic, not only 5.7.1
  2. Inspect authentication results and the sending domain state
  3. Separate domain policy from recipient-specific rejection
  4. Retest only after the specific cause in the diagnostic has been addressed

Best diagnostic path

Live analysis

Mail Failure Doctor

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

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.

Provider reference

For the provider-defined meaning and current requirements, review Gmail SMTP errors and codes.