What does "p=none" mean?

Monitor mode — the domain owner is collecting reports but not yet telling receivers to reject or quarantine unauthenticated mail. Fine as a starting point, not as a destination.

What should my DMARC policy be?

Start at p=none while you review DMARC aggregate reports. Once SPF + DKIM are aligned for all legitimate senders, move to p=quarantine, then p=reject.

DMARC Checker

Look up a domain's DMARC record with policy and reporting interpretation.

Check a domain's DMARC

DMARC record

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