Message-ID uniquely identifies an email message. Learn how it’s used for threading, de-duplication, and troubleshooting.
Message-ID is a header that uniquely identifies an email message. It’s used by clients to thread conversations and by systems to de-duplicate messages.
Message-ID also helps troubleshooting, especially when correlating logs across systems. Consistent, well-formed Message-IDs reduce odd behaviors in threading and filtering.
Related Keywords
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