deliverlensDelivery, deliverability, and placement: what each measures ↗
Choose the right evidence by distinguishing SMTP acceptance, mailbox placement, and longer-term recipient outcomes.
4 min readTechnical reference
Email deliverability articles
Understand SPF, DKIM, DMARC and sender reputation with clear technical explanations. Learn how to read email evidence and apply it to your next investigation.
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Softfail, fail, unknown, and unavailable are different outcomes ↗
Prevent operational errors caused by collapsing policy results and system failures into one status.
4 min readVisible From, MAIL FROM, and signing domain explained ↗
Understand the three common domain identities used in SPF, DKIM, and DMARC decisions.
4 min readDNS policy checks versus received-message authentication ↗
Know when a record lookup is sufficient and when the original received message is required.
4 min readVMC, CMC, and provider logo display decisions ↗
Separate evidence documents from provider-specific logo display decisions.
4 min readCatch-all, disposable, and role signals explained ↗
Interpret common verifier labels as bounded signals rather than final judgments.
4 min readWhy a not-listed result does not establish universal reputation ↗
Read blocklist coverage and negative results without overstating what was checked.
4 min readSeed observations versus actual audience behavior ↗
Understand what controlled seed tests reveal and what only real audience data can show.
4 min read