Knowledge base

Email Security Guides

Plain-English guides on DMARC, SPF, DKIM, and protecting your domain from spoofing.

What is DMARC and why does it matter?

DMARC (Domain-based Message Authentication, Reporting & Conformance) protects your domain from email spoofing and phishing. Learn what it is and how to set it up.

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How to set up SPF correctly

SPF (Sender Policy Framework) specifies which servers are allowed to send email for your domain. Learn how to create a correct SPF record step by step.

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SPF too many DNS lookups — how to fix it

SPF has a hard limit of 10 DNS lookups. Exceeding it causes email delivery failures. Learn why this happens and how to fix it.

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DKIM explained — a simple guide

DKIM (DomainKeys Identified Mail) adds a cryptographic signature to your emails so receivers can verify they were not tampered with. Here is how it works.

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DMARC p=reject vs p=quarantine vs p=none

Choosing the right DMARC policy is critical. Understand the difference between none, quarantine, and reject — and when to use each.

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How to check if your domain is vulnerable to spoofing

Anyone can spoof a domain without DMARC. Learn how to test your domain's email security and what the results mean.

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