Email That Actually Lands — In Plain English

Outlook doesn't hate you

Every week the phone rings and somebody says some version of: "Bill, my customer says they never got the invoice. I checked my Sent folder — it's right there." The honest answer is usually that the customer's email is doing exactly what it's supposed to do, and your domain is just missing the three little records that tell the rest of the internet you're the real you.

Since 2024, Google and Yahoo have required SPF, DKIM, and DMARC from anyone sending more than 5,000 messages a day to their users. In 2025 and 2026 they quietly tightened the screws for smaller senders too. Microsoft followed. If your domain doesn't have all three set up, your invoice has a coin-flip's chance of landing in the inbox — sometimes worse.

The three records, in one sentence each

• SPF — the guest list. A short list of which email servers are allowed to send mail using your domain. Anyone not on the list is treated as a forger.
• DKIM — the wax seal. An invisible digital signature on every email your domain sends. The receiver checks the signature against a public key in your DNS. If it matches, the email is genuinely from you and hasn't been tampered with.
• DMARC — the bouncer. Tells the receiving server what to do when SPF or DKIM fails (deliver anyway, send to spam, or refuse outright) and sends you a daily report of who's been trying to send mail as you.

What's in the 27-page PDF

• The 5-minute "is my email broken?" diagnostic — mxtoolbox, Google Toolbox, mail-tester.
• DNS, in three sentences (no airplane-cockpit jargon).
• SPF, DKIM, and DMARC, each in plain English, with the actual record strings.
• Click-by-click walkthroughs for the three DNS hosts where most small-business domains live: Cloudflare, GoDaddy, and Namecheap.
• The exact 15-minute setup for Google Workspace (SPF + DKIM in the admin console).
• The exact 15-minute setup for Microsoft 365 (the CNAME-not-TXT gotcha included).
• Adding your DMARC record — starting at p=none, ramping to p=reject without breaking anything.
• Reading the daily DMARC reports without going crazy — the free dashboards from Postmark and dmarcian.
• The "from" name, the subject line, and the spammy phrases that nuke delivery regardless of how good your DNS is.
• The six common mistakes Bill sees weekly (two SPF records is #1).
• When the problem isn't you — graylisting, blocklists, and the shared-IP problem.
• A one-page "is my email broken?" flowchart you can tape to the wall.
• The monthly email-health checklist.
• When to call Bill — what's quick over the phone, what needs a screen-share, what needs a visit.

Why I wrote this

A heating-and-cooling guy I help sends about 40 invoices a month. Before we fixed his SPF, DKIM, and DMARC, his average days-to-paid was 23. After we fixed them, it dropped to 12. That's not magic — it's that customers were finally getting the invoice on the first send, paying it that week, instead of him having to chase down each one a month later. On $14,000 of monthly invoicing, an 11-day faster collection is real cash flow.

Every guide on the internet about email authentication is written by sysadmins, for sysadmins, and reads like a stereo manual. This one's for the rest of us — the contractor, the bookkeeper, the shop owner who just wants the customer to actually get the invoice. No ads, no affiliate links, no fluff. Just what I'd hand to a friend who's losing jobs to the spam folder. — Bill