Outlook.com Is Quietly Rejecting Email From Domains Without DMARC
Summary
Outlook.com is rejecting emails from domains that do not publish a DMARC record, affecting small senders and not being widely announced by Microsoft. The article explains bounce behavior, why DMARC is becoming a baseline, and provides a quick DNS fix (publish a DMARC TXT record with v=DMARC1; p=none) plus guidance on verifying SPF/DKIM alignment and implementing DMARC for better deliverability.