SMTP verification
Mailbox check done over SMTP: connect, say hello, and ask RCPT TO. Done carefully so it is not a delivery, and not a burst that looks like an attack.
Mailbox check done over SMTP: connect, say hello, and ask RCPT TO. Done carefully so it is not a delivery, and not a burst that looks like an attack.
Also see: Mailbox check
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Mailbox check done over SMTP: connect, say hello, and ask RCPT TO. Done carefully so it is not a delivery, and not a burst that looks like an attack.
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- Mailbox check — cold email glossary
Asking the receiving server whether a specific local part is accepted. The only check that deserves the word verified.
- Cold email & deliverability glossary
Plain-language definitions for the terms that come up in cold outreach and email deliverability: bounce rate, catch-all, SPF/DKIM/DMARC, sender reputation, and more.
- Bounce rate — cold email glossary
The share of sent emails a mail server refuses to deliver. A hard bounce means the mailbox does not exist; a soft bounce means it is temporarily unreachable.
- Hard bounce — cold email glossary
A permanent delivery failure: the mailbox does not exist, the domain does not accept mail, or the server has rejected the recipient for good. Hard bounces are the ones that wreck sender reputation.