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Gabriel Sandru's avatar

One line to add to the authentication check: a DMARC record at p=none passes the requirement and protects nothing. Google and Yahoo have asked bulk senders, 5,000 messages a day, for SPF, DKIM and DMARC since February 2024, and Microsoft applied the same to Outlook consumer domains from May 2025. So the field worth reading in the DNS is the policy, not whether a record exists.

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