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Catch-all email detection, explained
If your verification tool says '99% valid' but you're still bouncing 15%, catch-all is the reason. Here's how it actually works.
What is a catch-all domain?
A mail server configured to accept every address regardless of mailbox existence.
Why SMTP probes return false positives
Catch-all servers always say '250 OK' even for fake addresses.
How we detect them
We test fake addresses against the same MX. If both succeed, the domain is catch-all.
What to do with catch-all leads
Send to them — but on a slow-send schedule and a separate sub-domain.
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