Guides d'authentification des e-mails
Des guides pratiques et sans détour sur SPF, DKIM et DMARC. Corrigez ce qui ne fonctionne pas et gardez vos e-mails hors du spam.
DMARC RUA vs RUF: Aggregate and Forensic Reports
A practical comparison of DMARC aggregate (rua) and failure/forensic (ruf) reports: what each contains, how often they arrive, why Google and Yahoo skip RUF for privacy reasons, and exactly which tags to add.
How to Read Email Headers to Check SPF, DKIM and DMARC
A practical walkthrough of email headers: how to open the raw source in Gmail, Outlook, and Apple Mail, then read the Received chain, Return-Path, and Authentication-Results to confirm SPF, DKIM, and DMARC or diagnose a failure.
2026 Bulk Email Sender Requirements: Google, Yahoo, Microsoft
The current 2026 checklist covering Gmail, Yahoo, Microsoft, and Apple bulk sender rules: SPF, DKIM, DMARC alignment, one-click unsubscribe, spam rate limits, and the enforcement timeline that now returns permanent rejections.
What Is Email Spoofing and How It Works
Email spoofing forges the visible From address by exploiting how plain SMTP separates the envelope from the message header. Learn how the forgery works, whether it is illegal, and how SPF, DKIM, and DMARC at p=reject actually stop it.
What Is Email Authentication? A Complete Guide
A plain-language pillar guide to email authentication: why open SMTP has no built-in identity, and how SPF, DKIM, DMARC, and supporting signals like PTR, ARC, BIMI, and MTA-STS work together to prove a message really came from your domain.
How to Set Up SPF, DKIM, and DMARC on GoDaddy Without Breaking Email
A step-by-step guide to configuring SPF, DKIM, and DMARC in the GoDaddy Domain Portfolio DNS panel. Learn how to merge multiple SPF includes into one record, avoid the @ versus host-prefix mistake, add records in the safe order so nothing bounces, and verify the result with a paste-ready DMARC starter policy.
How to Add SPF, DKIM, and DMARC Records in Cloudflare (Step-by-Step)
Add SPF, DKIM, and DMARC in Cloudflare DNS with exact dashboard clicks and paste-ready TXT values. Covers the traps that break setups: TXT records must be gray-cloud DNS only, Cloudflare auto-appends your domain so you enter _dmarc not the full hostname, and how the Email DMARC Management wizard differs from manual records. Then confirm authentication passes with the free spfwise checker.
How to Add SPF, DKIM, and DMARC Records in AWS Route 53
A precise walkthrough for adding SPF, DKIM, and DMARC records in AWS Route 53 using the Create Record flow. Covers correct TXT quoting, leaving the record name blank for the root SPF record, the _dmarc subdomain, how Amazon SES auto-publishes DKIM CNAMEs into your hosted zone, and starting DMARC at p=none before tightening. Verify the result with the SPFWise checker.
Postmark SPF, DKIM & DMARC Setup: The Complete Domain Authentication Guide
Postmark already makes SPF pass through its own Return-Path on mtasv.net, so the authentication work that actually matters for DMARC is the DKIM TXT record and a custom Return-Path CNAME to pm.mtasv.net. This guide explains why an SPF pass is not the same as SPF alignment, walks through both records in your DNS, sets a sensible DMARC policy, and shows how to confirm the finished result.
Brevo SPF, DKIM & DMARC Setup: Authenticate Your Domain (formerly Sendinblue)
Brevo authenticates your domain with DKIM, not SPF. On shared IPs the envelope sender stays on Brevo's domain, so SPF does not align to your From address, but Brevo signs mail with your domain and DMARC passes on DKIM alignment alone. This guide covers the brevo_code record, automatic and manual DKIM flows, the Sendinblue rename, the Gmail and Yahoo rules, and how to verify.
550 5.7.1 'Email Rejected Per DMARC Policy': Causes and Step-by-Step Fix
A 550 5.7.1 email rejected per DMARC policy bounce means the receiving server enforced your p=reject or p=quarantine policy because the message failed DMARC. This guide shows how to tell whether it is your own mail or a forgotten third-party tool, how to read the bounce, and how to add the missing SPF include or DKIM key instead of weakening your policy.
550-5.7.26 'Unauthenticated Sender' in Gmail: What It Means and How to Fix It
Gmail returns 550-5.7.26 when a message has no passing, aligned authentication. This guide decodes the exact wording and maps it to three fixable causes: neither SPF nor DKIM passing, an SPF or DKIM pass that does not align with your From domain, and a missing DMARC record. Includes a copy-paste diagnostic checklist and a free domain check that shows which of the three is failing.