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5.7.1 Delivery not authorized, message refused

The receiving server refused the message because of who sent it or how it looks. It is the most common “you are blocked” bounce, and the text after it tells you which kind.

5.7.1 Delivery not authorized, message refused

Permanent: retrying will not help

The receiving server refused the message because of who sent it or how it looks. It is the most common “you are blocked” bounce, and the text after it tells you which kind.

Usual causes
  • Your domain’s SPF, DKIM or DMARC checks failed. Gmail, Yahoo and Microsoft now require them for bulk senders.
  • Your sending address or domain is on a blocklist, or has a poor reputation.
  • The recipient only accepts mail from people they know, or from inside their organization.
  • Your message was judged to be spam.
What to do
  • Run your domain through the SendSend domain checker and fix whatever it flags.
  • Check blocklists for your domain and sending IP address.
  • Send from a domain you have set up properly, and ramp volume up slowly on a new one.
  • If the text says the recipient does not accept external mail, ask them to allow your address.

Usually the fault of: sender.

Common questions.

What does 5.7.1 mean?

The receiving server refused the message because of who sent it or how it looks. It is the most common “you are blocked” bounce, and the text after it tells you which kind.

Will retrying fix 5.7.1?

No. It is a permanent failure, so retrying the same message will not help, and repeated attempts can hurt your sending reputation. Fix the cause first.

How do I fix 5.7.1?

Run your domain through the SendSend domain checker and fix whatever it flags. Check blocklists for your domain and sending IP address. Send from a domain you have set up properly, and ramp volume up slowly on a new one. If the text says the recipient does not accept external mail, ask them to allow your address.

Other codes: 5.1.1 · 5.1.2 · 5.1.3 · 5.1.6 · 5.2.1 · 5.2.2 · 5.2.3 · 5.3.4 · Decode a whole bounce message

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