Hard bounce

Common causes are a mistyped address, a closed mailbox and a domain with no mail server. Remove a hard-bounced address from your list at once; retrying it only hurts your reputation.

Verification predicts hard bounces. An address marked invalid is one that would have hard-bounced.

• Bounce
• Bounce rate
• Email bounce handling
• Verify a list
• Topic: Email deliverability
• Topic: Email verification
• All terms