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  • DMARC

    How to Read and Act on DMARC Aggregate Reports: A Practical Guide

    DMARC aggregate reports tell you which sources send email for your domain and whether authentication checks pass or fail. Here is how to read the data and turn it into action.

    DMARCGuardian Editorial Team · August 5, 2026

  • DMARC

    DMARC Policies Explained: p=none, p=quarantine, and p=reject

    What DMARC policy tags actually do, what changes at each level, and how to move from p=none to p=reject without breaking your legitimate email.

    DMARCGuardian Editorial Team · August 5, 2026

  • DMARC

    DMARC Alignment: Strict vs. Relaxed Explained

    DMARC alignment determines whether your emails pass or fail authentication checks. Strict mode requires an exact domain match. Relaxed mode allows subdomains. Here is what the difference means in practice.

    DMARCGuardian Editorial Team · August 5, 2026

  • DMARC

    How to Configure DMARC in Microsoft 365 / Exchange Online: A Practical Guide

    Step-by-step guide to configuring DMARC for Microsoft 365 and Exchange Online, including DNS setup for SPF, DKIM, and DMARC records, plus how to read aggregate reports to safely tighten your policy.

    DMARCGuardian Editorial Team · August 5, 2026

  • DMARC

    How to Read DMARC Aggregate Reports: A Practical Field Guide

    DMARC aggregate reports arrive as dense XML files that most people never read. This guide explains what the data means, how to interpret the key fields, and what steps to take when your reports show authentication failures.

    DMARCGuardian Editorial Team · August 5, 2026

  • Why Third-Party Email Senders Break DMARC Alignment and How to Fix It

    Third-party email vendors like Proofpoint and Mimecast can break DMARC alignment even when SPF and DKIM pass. Here is why it happens and how to fix it.

    DMARCGuardian Editorial Team · August 5, 2026

  • DMARC

    What Email Security Grading Tools Actually Check: The Checklist Behind Your Domain Score

    Domain security grading tools evaluate SPF, DKIM, DMARC, and DNS configuration to assign letter grades. Here is exactly what they check and why most domains score in the C-to-F range.

    DMARCGuardian Editorial Team · August 5, 2026

  • DMARC

    What DMARC Verifies and What It Cannot Detect

    DMARC checks whether the sender domain matches your SPF and DKIM setup. It does not scan content, check URLs, or verify attachments.

    DMARCGuardian Editorial Team · August 5, 2026

  • DMARC

    Why the DMARC np Tag (RFC 9989) Does Not Work Reliably with DNSSEC

    The DMARC np tag (RFC 9989) conflicts with DNSSEC in a way that causes silent policy failures. Here is the technical explanation and what to use instead.

    DMARCGuardian Editorial Team · August 4, 2026

  • DMARC

    Are AI-Powered DMARC Tools a Security Risk?

    DMARC reports contain sensitive metadata about your entire sender ecosystem. Sending them to a cloud AI tool means sharing that data with third parties you may not fully control.

    DMARCGuardian Editorial Team · August 4, 2026

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