Soft bounce

The receiving server answers with a 4xx code, and your system retries for a while. If an address soft-bounces repeatedly over several sends, treat it as dead and suppress it.

Verification can return unknown where a server answers temporarily. Retry later rather than discarding the address.

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