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Email deliverability guides

Practical fixes for the SPF, DKIM and DMARC problems that actually break mail.

SPF "too many DNS lookups" — how to fix the 10-lookup limit

SPF fails silently once it needs more than 10 DNS lookups. Here is how to count your lookups, which mechanisms cost one, and four ways to get back under the limit.

DMARC p=none vs quarantine vs reject — which policy to use

What each DMARC policy actually does to your mail, how long to stay at p=none, and a safe rollout schedule to p=reject without losing legitimate email.

DKIM selector not found — why your DKIM check fails

DKIM keys hide behind a selector name you have to know. Here is how selectors work, the common selectors per provider, and how to find yours from a real email.

Google & Yahoo bulk sender requirements — the 2024 rules, still enforced

SPF, DKIM, DMARC, one-click unsubscribe and a spam rate under 0.3%. What each requirement means in practice and how to verify you meet them.

Why your email goes to spam — a diagnostic order of operations

Work the causes in the order that actually finds the problem: authentication first, then reputation, then content. With the checks for each.

How to set up DMARC — a step-by-step record you can copy

Publish a working DMARC record today: the exact DNS entry, what every tag does, and how to read the reports that come back.

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Reports for popular domains

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