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Changes between Initial Version and Version 1 of Ticket #64368, comment 66


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Timestamp:
12/15/2025 06:08:14 PM (6 months ago)
Author:
Monarobase
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  • Ticket #64368, comment 66

    initial v1  
    1 Not existing is invalid because RFC standards state that it's a mailbox.
     1RFC 5321 defines the SMTP envelope reverse-path (MAIL FROM / Return-Path) as “the sender mailbox” and states that the Return-Path’s primary purpose is to designate the address for non-delivery / failure reports.
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    3 If it's not existing then it's not a mailbox.
     3RFC 5322 defines a mailbox as an entity that receives mail (“A mailbox receives mail.”).  
     4Consequently, if the return-path value is undeliverable because it does not exist, it is not a mailbox in the RFC 5322 sense, and it defeats the RFC 5321 purpose of Return-Path handling. For non-DSN messages, RFC 5321 further states they SHOULD be sent with a valid, non-null reverse-path.  
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    5 Mailbox definition is here : https://datatracker.ietf.org/doc/html/rfc5321#section-2.3.11
     6RFC5321 :
     7https://datatracker.ietf.org/doc/html/rfc5321
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    7 SMTP defines the reverse-path (envelope MAIL FROM / what becomes Return-Path) as a sender mailbox
    8 RFC 5321 (SMTP) :
    9  - “The reverse-path consists of the sender mailbox.”
    10 https://datatracker.ietf.org/doc/html/rfc5321#section-4.1.1.2
     9RFCF322 :
     10https://datatracker.ietf.org/doc/html/rfc5322
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