Outlook.com

Microsoft's Outlook.com has begun rejecting incoming email from domains that lack DMARC records, a change flagged and widely discussed by email administrators. The move pushes senders to adopt authentication standards like SPF, DKIM and DMARC, which help prevent spoofing and phishing. Admins are debating whether the stricter policy improves security or unfairly blocks legitimate small domains that never set up DMARC.