MailConfigLab tool
MTA-STS Checker – Test Mail Transport Security
Check MTA-STS DNS configuration and policy readiness.
Get protocol evidence and practical recommendations from a focused DNS configuration check. Results describe public records and do not promise inbox placement.
What this tool checks
Check MTA-STS DNS configuration and policy readiness. The service validates the input server-side, queries the internal diagnostic engine and presents evidence without exposing infrastructure details.
How it works
Your request is sent through the application backend. The browser never contacts the internal DNS engine directly. Results are based on the current public DNS response and may change as records propagate.
Common problems
Typical findings include missing records, permissive policies, lookup limits, invalid syntax, unresolved hosts and incomplete enforcement.
FAQ
Do I need an account?
No account is required for the anonymous tool workflow.
Will this send email?
No. The tool reads DNS records and does not send reports or messages.
Are results permanent?
No. DNS and temporary report data can change or expire.