In Microsoft Exchange Server 2010, header firewall is a mechanism that removes specific header fields from inbound and outbound messages. Computers that are running Exchange 2010 that have the Hub Transport server role or the Edge Transport server role installed insert custom X-header fields into the message header.

Lets have a Closer look at this.

Server1, Server2 and Server3

When an Email is send from Server1 to Server3. Let us Assume it Went From Server1 to Server 2 and than to Server3

So Each Server’s which received the Email would ADD a RECEIVED header at the beginning of message header with a TimeStamp.

Here are headers from a message received from Dell. (Unnecessary headers removed).

(Errors By the Help of Bharat)

Received: from ( by
( with Microsoft SMTP Server id; Mon, 19 May 2008
03:12:46 -0700
Received: from ( []) by (Postfix) with ESMTP id 647C222914 for ;
Mon, 19 May 2008 06:14:46 -0400 (EDT)
Received: from [] ([] by (ecelerity r(19486)) with
ESMTP id 3B/AF-18306-11351384 for ; Mon, 19 May 2008
03:14:41 -0700</ME@SOMEDOMAIN.COM>
Message-ID: <>
Date: Mon, 19 May 2008 03:14:41 -0700
From: Dell Small Business
Subject: $429 desktop, plus new laptops. Hurry and shop now.

So Most Companies Don’t want the Names to be Published to People who Receive there emails.

Get-SendConnector "Connector Name" | Remove-ADPermission -AccessRight ExtendedRight -ExtendedRights "ms-Exch-Send-Headers-Routing" -user "NT AUTHORITY\Anonymous Logon"

More on this Can be Found here