The Deliverable Diary

Short version. If you’re not Amazon, not running your own postmaster team, and your inbox placement matters to your customers, SMTP2GO is the safest default. The 5 picks in 60 seconds If you don’t have time for the full piece, here’s the shortlist. Pick Best for Free plan Starts at Tested deliverability (2026) 1. SMTP2GO […]

Quick answer: DMARC is a small text record you publish in your domain’s DNS that tells receiving mail servers what to do if a message claiming to be from your domain fails SPF or DKIM checks. It does three things: it authenticates your outbound mail, it tells receivers how to handle failures (ignore, junk, or […]

If your emails are landing in spam, the cause is almost always one of seven things: missing or misconfigured authentication, a damaged sender reputation, a high complaint rate, a dirty or purchased list, a brand-new or cold-warmed domain, a content or link pattern that trips filters, or an SMTP provider that’s quietly making things worse. […]

A transactional email is an automated message triggered by something a specific person did, or something that happened to their account, and it carries information they’re expecting or that they need to complete an action. Receipts. Password resets. Shipping updates. Two-factor codes. The definition is the easy part. The interesting part is the line that […]

The rules quietly changed in February 2024. If your unsubscribe guide is older than that, it’s giving you 2014 advice for 2026 inboxes. Here’s what happened. Gmail and Yahoo started enforcing new requirements for any sender pushing more than 5,000 messages a day to their inboxes. One of those requirements: a working one-click unsubscribe, implemented […]

Most email attachment size guides give you a number and call it done. The problem is that the number on the box isn’t the number that actually sends. Encoding adds weight, recipient servers have their own caps, and a 24 MB file can bounce off a 25 MB limit without ever reaching an inbox. This […]