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Writing that delivers.

Deliverability guides and product notes — no filler.

Diagram of a mail server enforcing TLS via MTA-STS, with a STARTTLS downgrade attack blocked and TLS-RPT feedback
DeliverabilityJune 4, 2026

MTA-STS and TLS-RPT: encrypting mail in transit

How MTA-STS and TLS-RPT enforce encrypted mail delivery: what each record does, the DNS and policy-file setup, and a safe testing-to-enforce rollout.

Illustration of a DMARC aggregate report table listing four source IP addresses with green pass, amber warning, and red fail badges across SPF, DKIM, and DMARC columns.
DeliverabilityJune 3, 2026

How to read DMARC reports before you enforce

DMARC aggregate (rua) reports arrive as dense XML. Learn what they contain, how to spot legitimate sources failing alignment, and when to enforce.

Send volume ramping up gradually over time during a warmup
DeliverabilityJune 3, 2026

How to warm up a new email domain or IP

How to warm up a new email domain or IP: build reputation gradually so your first big send doesn't land in spam — the ramp and the pitfalls.

Diagram of a root domain example.com branching into transactional, marketing, and cold-outreach sending subdomains, each showing its own reputation status while the failing cold subdomain stays contained.
DeliverabilityJune 2, 2026

How an email sending subdomain protects your reputation

A dedicated email sending subdomain keeps a bad campaign from torching your transactional mail. Reputation isolation, SPF/DKIM/DMARC, and warm-up.

Diagram of three dormant subscriber rows: two re-engaged with green check marks and one moved to suppressed with an amber warning, above a sunset arc captioned 're-engage, then sunset the rest'.
DeliverabilityJune 1, 2026

Email list re-engagement: win back the dormant, protect the inbox

Re-engage dormant subscribers before they hurt deliverability: run a win-back campaign, set a sunset policy, and verify the list first.

Illustration of a Google Postmaster Tools dashboard: a spam-rate line chart creeping toward a dashed red 0.3% threshold, a High domain-reputation badge, and SPF, DKIM, and DMARC pass rates.
DeliverabilityMay 31, 2026

Google Postmaster Tools: read what Gmail really thinks

Google Postmaster Tools is Gmail's free sender dashboard. Verify your domain, read every metric, and act on spam rate and reputation.

A Microsoft SNDS data panel showing three sending IPs with green, yellow, and red filter results.
DeliverabilityMay 30, 2026

Microsoft SNDS and JMRP: measuring your Outlook reputation

Microsoft SNDS and JMRP show your per-IP volume, complaint rate, spam-trap hits, and green/yellow/red filter result for Outlook.com mail.

A shortlist of email verifiers compared as DeBounce alternatives, with one highlighted as the recommended pick
GuidesMay 30, 2026

The best DeBounce alternatives in 2026, compared

DeBounce is cheap but charges extra for catch-all. The best alternatives compared on price, EU data, and catch-all handling — with sourced facts.

Seed panel listing per-provider placement results: Gmail inbox, Outlook spam, Yahoo inbox, corporate missing.
DeliverabilityMay 29, 2026

Inbox placement testing: what seed tests really prove

A seed test previews where your campaign lands across Gmail, Outlook and Yahoo — inbox, spam, or missing. What it measures and its limits.

Cloudflare DNS editor adding a TXT record, with the Name field mapped to @ for SPF, a selector for DKIM, and _dmarc for DMARC.
DeliverabilityMay 28, 2026

How to set up SPF, DKIM, and DMARC in Cloudflare

Set up SPF, DKIM, and DMARC in Cloudflare DNS: where to add each TXT record, what to enter in the Name field, and how to verify it works.

A GoDaddy 'Add new record' DNS form showing a TXT record with @ in the Name field, above pills for the three Name-field values: @ for root, _dmarc, and selector._domainkey.
DeliverabilityMay 27, 2026

Set up SPF, DKIM, and DMARC in GoDaddy

Add SPF, DKIM, and DMARC records in GoDaddy DNS: find the editor, use the @ Name-field convention, then verify. Step-by-step 2026 guide.

A code window where a regex-approved address still returns undeliverable
EngineeringMay 27, 2026

Why regex email validation fails

Regex validates syntax, not deliverability — valid-looking addresses still bounce. Why regex email validation fails, and the layered check that works.