How can I display FULL HEADERS of incoming messages?

Besides the basic information like the addresses of the sender (From:) and the recipient (To:), the subject (Subject:) and the date (Date:), the Full Mail Headers is the complete set of Email headers added by the sender's email software and related Mail Servers during the email delivery process. It contains very useful information of the email message delivery and routing, including IP addresses involved, time sent and the sources of the email. For more detailed explanation of Email headers please refer to this document.

The following are the Full Message Headers of a sample message:

Return-path: <>
Received: from ( [])
by (iPlanet Messaging Server 5.1 (built May 7 2001))
with ESMTP id <>; Wed, 17 Apr 2002 12:13:08 +0800 (CST)
Received: (from root@localhost) by (8.10.2+Sun/8.10.2)
id g3H4D2C14160; Wed, 17 Apr 2002 12:13:02 +0800 (CST)
Date: Wed, 17 Apr 2002 12:13:02 +0800 (CST)
From: University Publications Office <>
Subject: [EBS] CityU Today Issue No. 16
To: Email Broadcast System Message 0000011930 <>
Reply-to: University Publications Office <>
Message-id: <>
MIME-version: 1.0
Content-type: multipart/mixed; boundary="Boundary_(ID_0C97v+RWNdqo2jzJ0egUww)"

Please refer to the following steps to display full headers of your message.

A) Using Microsoft Outlook for Windows

B) Using Microsoft Outlook for Mac

C) Using Microsoft 365 Outlook Web App (OWA - Microsoft 365 Webmail)


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