<b>Best of the inbox: authentication, settled</b>

<b>Best of the inbox: authentication, settled</b>
SPF, DKIM, DMARC trip up more affiliate senders than any creative ever will. The best explainers, ranked by how fast they get you to a working record.

🔐 Auth
— dmarcian's DMARC overview — the cleanest mental model of why the Header-From domain is what actually gets checked. Picked it for the alignment diagrams alone.
— Google's bulk-sender FAQ — short, official, and the source of the 5,000/day threshold everyone quotes wrong. Read it directly, not the blog summaries.
— EasyDMARC's record generator — gets you from p=none to p=quarantine without hand-editing TXT records.

🧰 Tooling
— MXToolbox SuperTool — one box, every DNS lookup; the bookmark you'll use weekly.

Saved you ~2 hours of conflicting Stack Overflow threads. Start at p=none and read your reports for two weeks before tightening.