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    Chat Approvals Are Not Change Control: The Right Way to Handle SPF DKIM and DMARC DNS Changes

    Treating SPF, DKIM, and DMARC as "just TXT records" to add via chat has ended campaigns, tanked domain reputations, and opened domains to spoofing. Here is the minimum change control process for email authentication DNS changes.

    DMARCGuardian Editorial Team · June 25, 2026

  • DMARC

    Why moving to DMARC p=reject without monitoring is a recipe for mail failure

    Flip DMARC from p=none to p=reject without a sender inventory or aggregate report monitoring, and legitimate email stops arriving. Here is what actually breaks and how to migrate safely.

    DMARCGuardian Editorial Team · June 25, 2026

  • DMARC

    How to Catch Your Own DMARC Mistakes Before Attackers Exploit Them

    Your DMARC reports expose the configuration gaps attackers look for. Here is how to catch your own subdomain authentication mistakes before they silently block your mail or get exploited.

    DMARCGuardian Editorial Team · June 24, 2026

  • DMARC

    What Happens When a Subdomain Has DMARC p=reject But No SPF Record

    When a subdomain inherits p=reject but has no SPF record, legitimate mail fails silently. Here is the exact failure chain and how to find the gaps before they cause an outage.

    DMARCGuardian Editorial Team · June 24, 2026

  • DMARC

    What Breaks When You Move to DMARC p=reject Without Monitoring Tools

    Flipping DMARC from p=none to p=reject without aggregate report monitoring or prior expertise will break legitimate mail. Here is what goes wrong, why reports are essential, and how to move safely.

    DMARCGuardian Editorial Team · June 24, 2026

  • DMARC

    What Your SEG Catches When BEC Gets Through: A Detection Guide

    SEG products miss payloadless BEC attacks because traditional content scanning has nothing to flag. This guide explains what your SEG catches, what slips through, and how to close the detection gap with authentication-based monitoring.

    DMARCGuardian Editorial Team · June 23, 2026

  • SPF

    How to Find and Fix Orphaned SPF Records on Abandoned Campaign Mail Subdomains

    When a campaign subdomain's ESP account is closed but the SPF record remains, your domain is exposed to abuse. This guide explains how to find orphaned SPF records using DMARC reports and DNS audits, fix them, and monitor automatically so they do not happen again.

    DMARCGuardian Editorial Team · June 23, 2026

  • DMARC

    Can You Forward DMARC Reports to a Third-Party Aggregation Service?

    <p>DMARC reports can be forwarded to third-party aggregation services without breaking report integrity, provided the forwarding path preserves the original MIME structure.</p>

    Editorial Team · June 16, 2026

  • DMARC

    How to move from p=none to p=reject without breaking your email

    <p>A step-by-step guide for M365 admins moving from DMARC p=none to p=reject without breaking legitimate email delivery.</p>

    Editorial Team · June 12, 2026

  • DMARC

    Why Your Users Keep Reporting Legitimate Password Reset Emails as Phishing

    <p>Password reset emails pass DKIM but still get reported as phishing because the reset link domain does not match the From address brand. This is a structural mismatch, not a training failure.</p>

    Editorial Team · June 12, 2026

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