THE TOPIC DESK / SEPTEMBER 2026
Email deliverability fieldnotes
Practical guides for inbox placement, spam testing, authentication and pre-send decisions. Start with the signal you need to understand.
PRACTICAL GUIDE
Inbox placement testing: read the result in context ↗
Learn how to interpret an inbox placement test, distinguish seed results from real audience outcomes and keep a useful baseline for repeat investigations.
PRACTICAL GUIDE
Email spam testing: turn warnings into a checklist ↗
A practical email spam-testing workflow: check configuration, inspect the message and investigate placement without treating a score as a delivery guarantee.
PRACTICAL GUIDE
SPF, DKIM and DMARC: a practical sender map ↗
Understand the roles of SPF, DKIM and DMARC, then build a safe sender inventory before changing DNS. Authentication is not a guarantee of inbox placement.
PRACTICAL GUIDE
How to read DMARC reports without guessing ↗
Start with sender ownership, time windows and authentication results when reviewing DMARC aggregate reports. Use a triage worksheet before changing policy.
PRACTICAL GUIDE
Gmail sender requirements: an operational checklist ↗
Review Gmail sender requirements with a practical ownership checklist for authentication, unsubscribe behavior and monitoring. Verify Google’s current rules.
PRACTICAL GUIDE
Pre-send email checklist: a repeatable test protocol ↗
A practical pre-send email checklist for sender identity, audience expectations, message checks and placement tests. Record one baseline and a clear go/no-go.
PRACTICAL GUIDE
How to use GlockApps: a controlled first test ↗
Learn how to use GlockApps Inbox Insight for a controlled manual email test, preserve a baseline and interpret results without overclaiming.