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Author Topic: Header Return-Path  (Read 119314 times)


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Header Return-Path
« on: January 10, 2019, 05:07:32 PM »

Hi, what is the best configuration to header return-path

At this moment we use the same for all ips of X.X.X.X/24

ie: Return-Path : <name@subdomain.domain.com>

It's fine??

Or we should use <name@subdomain1.domain.com> ( X.X.X.1)
<name@subdomain2.domain.com> ( X.X.X.2)
<name@subdomainN.domain.com> ( X.X.X.N)

where  subdomainN.domain.com is the RNDS for the ip X.X.X.N



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  • Hasan Kurtoglu
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Re: Header Return-Path
« Reply #1 on: January 10, 2019, 05:37:17 PM »

As long as you dont change the domain itself,changing the subdomain on returnpath wont change anything in terms of reputation.

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Re: Header Return-Path
« Reply #2 on: January 11, 2019, 04:22:13 PM »



Maarten Oelering

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Re: Header Return-Path
« Reply #3 on: February 14, 2019, 05:55:32 AM »

It's a common mistake to think that a sender should insert a Return-Path header.

Receivers use the envelope sender in MAIL FROM command to return asynchronous/remote bounces. The Return-Path header is inserted by receivers to preserve the envelope sender when it is delivered via other means than SMTP. See section 4.4 in RFC 5321, the "SMTP standard":

   When the delivery SMTP server makes the "final delivery" of a
   message, it inserts a return-path line at the beginning of the mail
   data.  This use of return-path is required; mail systems MUST support
   it.  The return-path line preserves the information in the <reverse-
   path> from the MAIL command.  Here, final delivery means the message
   has left the SMTP environment.  Normally, this would mean it had been
   delivered to the destination user or an associated mail drop, but in
   some cases it may be further processed and transmitted by another
   mail system.