The Kalenfy blog

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Guides on SPF · DMARC · DNSSEC & more — then scan your site free

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

27 June 2026

Is My Domain Spoofable? (Free Spoofing Test)

Find out in seconds whether someone can send email pretending to be your domain. A free spoofing test that checks your SPF, DKIM and DMARC — and how to lock it down.

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Guides & checklists

27 June 2026

Email Security & Compliance: What's Actually Required

Is DMARC required? What do GDPR, PCI and Google/Yahoo actually demand for email security? Here's what compliance really means for your domain — and how to prove you meet it.

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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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Email authentication

27 June 2026

How to Get Your Logo in Gmail (BIMI Setup)

Want your brand logo to show next to your emails in Gmail? That's BIMI. Here's what it needs (DMARC at enforcement first), how to set it up, and how to check your domain 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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Email authentication

27 June 2026

How to Set Up DKIM on Google Workspace & Microsoft 365

Step-by-step guide to enabling DKIM on Google Workspace and Microsoft 365, publishing the key in DNS, and verifying it passes — with a free check of your domain.

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Fixes & troubleshooting

27 June 2026

DMARC p=none vs reject: Moving Safely to Enforcement

DMARC at p=none only monitors — it doesn't stop spoofing. Here's the difference between p=none, quarantine and reject, and how to move to enforcement without blocking real mail.

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Email authentication

27 June 2026

Someone Is Sending Email From My Domain — How to Stop It

Getting bounce-backs or reports of spam 'from you'? Someone is likely spoofing your domain. Here's how to confirm it and stop it fast with DMARC — plus a free check.

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Fixes & troubleshooting

27 June 2026

DKIM Fail: How to Troubleshoot and Fix It

Seeing dkim=fail or 'DKIM signature invalid'? Here's why DKIM fails — wrong selector, broken key, alignment — and how to fix it, with a free check of your domain.

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Guides & checklists

27 June 2026

Email Security Audit for Small Business (Free Checklist)

A free email security audit for your small business — check SPF, DKIM, DMARC, DNSSEC and more in one scan, see your grade, and fix what's exposed before attackers find it.

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