📖 Glossary
What is Hard Bounce?
An email that has failed to deliver for permanent reasons, such as the recipient address being invalid or the domain name not existing.
Detailed Explanation
A hard bounce is a permanent delivery failure. When an email bounces hard, the receiving server explicitly states that the recipient does not exist or the domain is invalid. Sending emails to addresses that consistently hard bounce will severely damage your sender reputation. Best practices dictate removing hard bounces from your mailing list immediately. ZeroBounce AI detects these invalid addresses before you send, protecting your reputation.
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