Why do some emails show “Authenticated by XYZ” even with DMARC fail?

Mailbox providers often display results from the Authentication Results header defined in RFC 8601. This header may show spf=pass or dkim=pass which the interface highlights even when the final dmarc=fail due to non alignment is the result that determines policy.

DMARC is alignment based. User facing labels are not.

Was this answer helpful?

Thanks for your feedback!