DMARC can be configured with different options in regards to the policy. By implementing a policy, you're telling mail servers all around the world how to handle unauthorized use of your domain's email. You could strictly monitor email traffic, quarantine email traffic to be on the safe side, or completely reject all unauthorized messages.
DMARC None or Ignore - This policy instructs receiving mail servers to take no action based on the DMARC evaluation results. It allows domain owners to monitor email traffic without impacting the delivery of messages.
DMARC Quarantine - Under this policy, emails failing DMARC authentication are sent to the spam or quarantine folder, rather than being delivered to the recipient's inbox. This provides an intermediate level of protection against potentially malicious emails while still allowing for delivery.
DMARC Reject - The strictest of the three, this policy instructs receiving mail servers to outright reject emails failing DMARC authentication. These emails are not delivered to the recipient's inbox and are typically returned to the sender or discarded entirely.
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