DMARC's Reject Policy Explained
"p=reject"
The most stringent of the DMARC policies, the "p=reject" selector offers robust protection against email spoofing and phishing attacks by instructing recipient mail servers to outright reject emails that fail DMARC authentication. These rejected emails are typically returned to the sender (bounced) during the SMTP handshake, ensuring they don't reach the intended recipients' inboxes. This policy helps ensure that only emails authenticated using SPF (Sender Policy Framework) and DKIM (DomainKeys Identified Mail) pass through to recipients' inboxes, thereby reducing the risk of malicious emails reaching users
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