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The mail message will contain these headers from the original SMTP server in addition to others appended by other servers that has handled the mail.
Received: from o1.distribution.meridix.eu (198.21.7.95)
Sender: [the name and sender address definied in Meridix Studio]
From: [the name and sender address definied in Meridix Studio]
To: [the target receiver email]
Return-Path: bounces{custom id identifying the mail for logging if delivery fails, including the recipient mail address}@distribution.meridix.eu
Note that the Return-path (distribution.meridix.eu) domain is not pointing to the same domain (or IP) as the Received header (o1.distribution.meridix.eu).
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