DMARC Subdomain Policy: How sp= Overrides Your Main Record
Your root domain can sit at p=reject while every subdomain underneath it stays wide open.
Read more →Email Deliverability Blog
Practical guides on staying out of the spam folder: blacklists, SPF/DKIM/DMARC, and sender reputation. Written when we have something worth publishing — not on a schedule.
Google Postmaster Tools vs. DNS Blacklist Monitoring
Google Postmaster Tools and DNS-based monitoring look like they measure the same thing. They don't. Here is what each one actually shows you.
Read more →Multiple SPF Records: Why Two TXT Entries Break Mail
Two SPF TXT records on one domain do not add up — they cancel each other out and break authentication for everyone sending on your behalf.
Read more →Shared IP Reputation: Why a Neighbor's Spam Blacklists You
Your SPF, DKIM, and DMARC all pass, yet you're still blacklisted. The cause may not be your domain at all — it may be another sender on the same shared IP address.
Read more →Missing PTR Record: Why Your Mail Gets Blacklisted
A missing or mismatched PTR record is one of the quietest ways mail lands in spam. Here is how to check it and fix it before a receiving server blocks you.
Read more →DKIM Selector Missing? Your Provider May Use a Custom One
A deliverability check can say DKIM is missing even when it is correctly published, because the check does not know your selector. Here is how to find yours.
Read more →SPF Soft Fail vs Hard Fail: A Practical Decision Guide
Your SPF record ends in ~all or -all, and that one character decides whether forged mail gets flagged or rejected outright before it reaches an inbox.
Read more →Gmail and Yahoo Bulk Sender Rules: The DNS Checklist
Gmail and Yahoo now require authenticated mail and a low complaint rate from any domain sending 5,000+ messages a day. Here is the DNS checklist and how to keep passing it.
Read more →Email Health Score Explained: What 80 and 50 Really Mean
Your domain has a health score and you have no idea what the number means. Here is exactly what moves it, and what to fix first.
Read more →DKIM Key Rotation: How Often Should You Really Do It
Most domains publish one DKIM key and never touch it again. Here is how often to rotate it and how to roll it over without a single message failing signature checks.
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