SMTP Bounce Codes

What is SMTP Bounce Codes?

Simple Mail Transfer Protocols (SMTP) are codes sent to you from various mail servers, showing the reasons emails you sent were rejected. They help identify the reasons your emails bounced and are sometimes demanded by your email validation service providers to understand what causes your bounces.

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• Domain-Based Message Authentication, Reporting, and Conformance (DMARC)
• BIMI
• Domain
• Mail Transfer Agent (MTA)
• Bulk Folder
• Canonical Name (CNAME)
• Bounce Handling
• Denial-of-Service Attack or List-Bomb Attack