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Guides

DMARC, SPF, DKIM and email security guides

Step-by-step walkthroughs, explainers and troubleshooting for email authentication, DNS and domain security. Written for busy IT teams and UK MSPs.

Showing 26 of 52 resources

Guide

Bulk Sender Requirements 2026: Google, Yahoo and Microsoft

What Google, Yahoo and Microsoft require from bulk senders in 2026: SPF, DKIM, DMARC alignment, one-click unsubscribe and spam-rate limits, mapped to the DNS controls that satisfy them.

Guide

DMARC for MSPs: Managing Email Security Across Client Domains

An operational playbook for UK MSPs running DMARC across many client tenants: auditing, bulk onboarding, per-client white-label reporting, alignment and pricing that scales.

Guide

How to Move from DMARC p=none to p=reject (Step by Step)

A report-driven path from p=none to p=reject: read the aggregate reports, authorise every legitimate sender, then advance to quarantine and reject once the data is clean.

Guide

Free DMARC Tools Compared: Checkers, Generators and Report Viewers

An honest map of the free DMARC tool landscape in 2026, what each one really gives you, the limits of free tiers, and when a multi-domain team should move to a paid platform.

Guide

DMARC for Parked Domains: Lock Down Non-Sending Domains

How to set up DMARC for a parked domain that never sends email. NULL MX, SPF -all, p=reject and DKIM revocation, with RFC, NCSC and M3AAWG sources.

Guide

Best DMARC Monitoring Tools UK 2026

UK-focused 2026 comparison of ShieldMarc, dmarcian, EasyDMARC, PowerDMARC, Valimail, Red Sift and Sendmarc. Pricing, features, data residency and best fit for UK MSPs, multi-domain IT teams, NHS trusts and enterprise.

Guide

How to Set Up DMARC for Google Workspace

Step-by-step guide to configuring DMARC, SPF, and DKIM for Google Workspace. Protect your domain from spoofing and improve Gmail deliverability.

Guide

How to Set Up DMARC for Microsoft 365 (Office 365)

Step-by-step guide to configuring DMARC, SPF, and DKIM for Microsoft 365. Protect your organisation from email spoofing and improve deliverability.

Guide

What is BIMI? Brand Indicators for Message Identification Explained

How BIMI displays your verified logo in Gmail, Apple Mail, and Yahoo, and what a VMC actually costs.

Guide

DMARC p=quarantine vs p=reject: Which Policy Should You Use?

When to pick quarantine, when to pick reject, and how to move between them without breaking mail flow.

Guide

DMARC for the NHS and UK Public Sector: A Post Mail Check Guide

How NHS trusts, councils, and gov.uk bodies can replace NCSC Mail Check with a UK owned, EU hosted platform.

Guide

What is DMARC? A Plain English Guide

DMARC explained for IT teams. What it does, how it works, and why you need it.

Guide

SPF vs DKIM vs DMARC: What's the Difference?

How SPF, DKIM, and DMARC work together to protect your domain from spoofing.

Guide

Understanding DMARC Reports: RUA and RUF Explained

How to read and act on DMARC aggregate and forensic reports.

Guide

SPF Hard Fail vs Soft Fail: Why ~all Is Safer with DMARC

When to use -all vs ~all in your SPF record and how DMARC changes the equation.

Guide

How to Fix SPF Too Many DNS Lookups

Diagnose and fix the 10 DNS lookup limit in SPF records.

Guide

NCSC Mail Check Has Retired: What UK Organisations Should Do Now

What the NCSC Mail Check retirement means and how to replace it.

Guide

SSL Certificate Monitoring: What to Check and When

Avoid certificate expiry incidents with proactive SSL monitoring.

Guide

What is MTA-STS and TLS-RPT? Securing Email in Transit

How MTA-STS enforces TLS for inbound email and TLS-RPT captures delivery failures.

Guide

What is DNSSEC? How DNS Signing Protects Your Domain

How DNSSEC prevents DNS spoofing and cache poisoning attacks.

Guide

CAA Records Explained: Control Who Issues Your SSL Certificates

Use CAA records to restrict which certificate authorities can issue certs for your domain.

Guide

DNS Record Types Explained: A, AAAA, MX, TXT, CNAME and More

A guide to every common DNS record type and what it does.

Guide

Domain Expiry and WHOIS: How to Protect Your Registration

Prevent domain hijacking and accidental lapses with registration monitoring.

Guide

Protecting Your Brand from Lookalike Domains

Detect and defend against typosquatting and brand impersonation domains.

Guide

How to Create SPF, DKIM, and DMARC Records: Step-by-Step

A step-by-step walkthrough for setting up email authentication from scratch.

Guide

How to Set Up DKIM: Step-by-Step for Every Email Provider

Provider-specific DKIM setup guides for Google Workspace, Microsoft 365, SendGrid, Mailchimp, and more.