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  • SPF

    How to Find and Stop Exchange Server Mystery Forwarding Before It Becomes a Data Leak

    Exchange Server can forward mail to external addresses through inbox rules, transport rules, or mailbox settings you did not configure. Here is how to find them and stop them.

    DMARCGuardian Editorial Team · July 5, 2026

  • DMARC

    What DANE Adoption Data Reveals About the State of Email Authentication in 2026

    Monthly tracking across the top 1 million domains shows DANE adoption fell in month two of measurement, and the reason reveals how provider decisions, not protocol quality, drive email authentication adoption.

    DMARCGuardian Editorial Team · July 5, 2026

  • DMARC

    How Attackers Use Device Code Authentication to Bypass Microsoft 365 Phishing Defenses

    OAuth device code flow (RFC 8628) is a legitimate Microsoft authentication method that attackers now abuse to steal M365 sessions. Here is how the attack works, why traditional email security misses it, and what controls catch it before session tokens are issued.

    DMARCFlow Editorial Team · July 5, 2026

  • DMARC

    How to Move DMARC to p=reject Safely When Your Organization Has No Prior Email Authentication Experience

    A practical step-by-step guide for IT teams with no email authentication background to move from p=none to p=reject without breaking inbound email.

    DMARCGuardian Editorial Team · July 5, 2026

  • DMARC

    How to Move DMARC to p=reject Safely (When Your Team Has No Email Authentication Experience)

    Moving DMARC to p=reject without knowing what your own servers send will break legitimate email. Here is the three-phase approach that makes it safe, even for teams with no prior email authentication experience.

    DMARCGuardian Editorial Team · July 5, 2026

  • DMARC

    How to move to DMARC p=reject when legacy copiers are blocking your policy

    Legacy copier scan-to-email often lacks aligned SPF or DKIM, silently blocking your move to DMARC p=reject. Here is how to find every affected device and the three practical paths to a fix.

    DMARCGuardian Editorial Team · July 4, 2026

  • DMARC

    What to Do When a Third-Party Email Security Gateway Starts Rejecting Your DMARC-Aligned Mail

    Your mail passes DMARC directly but fails when routed through a third-party gateway such as Proofpoint. Here is why it happens and how to fix the alignment gap.

    DMARCGuardian Editorial Team · July 4, 2026

  • DMARC

    Why Email Security Adoption Moves in Provider-Sized Blocks (and Why That Matters for Your Domain)

    One provider removing DANE records knocked 500 domains off the protocol in a single month. Here is what the data shows about how email security actually spreads.

    DMARCGuardian Editorial Team · July 4, 2026

  • DMARC

    Why Email Scams Scale Because of Broken Identity Infrastructure, Not Gullible Users

    Email scams scale not because users are easily fooled, but because the infrastructure that should verify sender identity was never designed to do it. Here is what actually needs to change.

    DMARCGuardian Editorial Team · July 4, 2026

  • DMARC

    Email Authentication Adoption Trends: What the Monthly Top-1M Domain Measurement Reveals About DANE, BIMI, and MTA-STS

    Monthly measurements across the top 1 million domains show MTA-STS growing while DANE slipped. Here is what the trends mean for your email security roadmap.

    DMARCGuardian Editorial Team · July 4, 2026

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