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Dead Domain Detection — Identify domains that produce hard bounces before sending. Check Domain Health →

What is a dead domain?

A dead domain is a domain that no longer hosts an active website or functioning mail system. DNS entries may exist but they do not resolve to usable services. Sending to dead domains produces hard bounces with five xx SMTP codes such as five five zero Host unknown or five point one point two because there is no Mail Transfer Agent available to receive mail.

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