Practical guides to domains that must work.
Why each part of DNS, email authentication and monitoring matters — what breaks when it is missing, and how to check yours in under a minute.
How to Read a Domain Health Report and What to Fix First
A score is only useful if it tells you what to do next. Here is exactly how the StatusDNS health score is calculated, and the order to work through the findings.
Read the guide →Making SMTP Encryption Something You Can Rely On
STARTTLS is optional by design, and anyone in the network path can remove the offer. MTA-STS and TLS-RPT turn "we probably used TLS" into something you can require and verify.
Read the guide →The Bulk Sender Checklist for Gmail, Yahoo and Microsoft
Since February 2024 the large mailbox providers stopped treating authentication as optional. Here is the full checklist and what happens when you miss an item.
Read the guide →Why Mail Servers Judge Your IP by Its PTR Record
Reverse DNS is the one mail setting you cannot fix in your own DNS zone. Here is what receivers check, why a missing PTR costs you delivery, and how to get one.
Read the guide →Who Changed That DNS Record?
Zones drift — agencies, ex-vendors, a developer "just testing". Most changes are harmless and one is a hijack. You cannot tell them apart without a baseline.
Read the guide →Why Checking Once Is Not the Same as Monitoring
A green check is a statement about one moment. Most domain failures happen quietly afterwards — here is how to think about detection time, and what to watch.
Read the guide →Your Certificate Renewed. It Just Never Reached the Server.
Renewal is not deployment. The classic outage is a certificate issued perfectly on time, sitting on disk, while the running service still serves the expired one.
Read the guide →From p=none to p=reject Without Breaking Your Mail
Publishing an enforcing policy on day one is how legitimate mail disappears. Here is the staged path, plus what to do about forwarding and mailing lists.
Read the guide →The Outage Nobody Plans For: Your Domain Expires
A lapsed domain takes down your website, your email and every login at once — and it almost always happens because of an expired card, not a decision.
Read the guide →The SPF 10-Lookup Limit and the Silent PermError
Add one more vendor to your SPF record and mail can start failing for everyone — with no bounce, no error in your sending dashboard and nothing in your logs.
Read the guide →How Email Blacklists Work, and How to Get Off One
A blacklist listing stops your mail at the door, usually without warning. Here is how listings happen, what they cost, and how to get removed without being re-listed a week later.
Read the guide →SPF, DKIM and DMARC: How a Receiver Actually Decides
Follow one message from your server to somebody's inbox and see exactly where each protocol is consulted — and why two out of three is often the same as none.
Read the guide →Stop reading, start checking.
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