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DNS & domain security

All our dns & domain security guides

All Email authentication DNS & domain security Fixes & troubleshooting Guides & checklists
DNS & domain security

27 June 2026

How to Set Up MTA-STS (Encrypt Inbound Mail)

MTA-STS forces inbound email to your domain over encrypted TLS, blocking downgrade attacks. Here's what it is, how to set up the policy and TLS-RPT, and how to check it free.

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DNS & domain security

27 June 2026

How to Protect Parked & Non-Sending Domains from Spoofing

Own domains that don't send email? They can still be spoofed. Here's how to lock down parked and non-sending domains with SPF, DMARC and a null MX — checked free.

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DNS & domain security

27 June 2026

Wildcard DNS & Subdomain Takeover: The Hidden Risk

Wildcard DNS and dangling records can let attackers hijack your subdomains for phishing. Here's how subdomain takeover works, the warning signs, and how to check your domain free.

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DNS & domain security

27 June 2026

What Is a CAA Record (and How to Add One)?

A CAA record controls which certificate authorities can issue SSL certificates for your domain. Here's what it is, why it matters, and how to add one — with a free check.

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DNS & domain security

27 June 2026

What Is DNSSEC and Why Your Domain Needs It

DNSSEC explained simply: what it is, the DNS spoofing and cache-poisoning attacks it prevents, how to check if DNSSEC is enabled, and how to turn it on for your domain.

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