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  • SPF

    SPF include vs redirect — the Practical Difference

    Both include and redirect delegate your SPF record to another domain. They sound similar. They behave very differently.

    DMARCGuardian Editorial Team · August 26, 2026

  • Deliverability

    What Percentage of Mail Servers Refuse Email Without TLS? A Data-Driven Look

    Most major email providers enforce TLS encryption, but the wider internet is patchier. Here is what the data shows and what it means for your mail server configuration.

    DMARCGuardian Editorial Team · August 26, 2026

  • Deliverability

    What Actually Breaks When Your Domain Expires (And How to Prevent It)

    When a domain expires, email stops working in ways most administrators never anticipate. This guide covers exactly what breaks, why, and how to prevent it before it happens to you.

    DMARCGuardian Editorial Team · August 26, 2026

  • Deliverability

    How to Stop Backscatter NDR Emails from Your Server

    Backscatter NDRs are bounced spam notifications your server sends to innocent people. Here is exactly why they happen and how to configure your mail server to stop generating them.

    DMARCGuardian Editorial Team · August 26, 2026

  • DMARC

    When SPF and DKIM Pass But DMARC Fails: What It Means and What to Do

    SPF and DKIM passing but DMARC failing means the email authenticated but failed alignment checks. Here is what that actually means for trust.

    DMARCGuardian Editorial Team · August 26, 2026

  • DMARC

    Why SPF and DKIM Pass But DMARC Alignment Still Fails

    When SPF and DKIM both pass but DMARC fails, the issue is not authentication but alignment. DMARC checks that the From domain matches the domain that passed SPF or DKIM. Here is why that matters and how to fix it.

    DMARCGuardian Editorial Team · August 26, 2026

  • DMARC

    Why Your DMARC Aggregate Reports Are Not Arriving (and How to Fix It)

    Setting up DMARC reporting but getting no reports? This guide walks through every common reason RUA aggregate reports stop arriving and how to fix each one.

    DMARCGuardian Editorial Team · August 26, 2026

  • DMARC

    How to Protect High-Risk Executive Inboxes Without Breaking the Bank

    Small teams can protect executive email accounts from impersonation and compromise without enterprise budgets. Here is what actually reduces risk, ranked by impact.

    DMARCGuardian Editorial Team · August 26, 2026

  • DMARC

    How to Check SPF, DKIM, and DMARC Records for Any Domain

    A practical guide to checking SPF, DKIM, and DMARC records using dig, nslookup, and free online tools like MXToolbox.

    DMARCGuardian Editorial Team · August 25, 2026

  • DMARC

    Why DMARC Fails on Forwarded Email and How to Fix It

    Forwarded emails often fail DMARC because forwarding rewrites the From header, breaking SPF and DKIM alignment. Here is why it happens and what to do about it.

    DMARCGuardian Editorial Team · August 25, 2026

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