A Weblog About Topics and Issues Discussed in the Book Spam Kings by Brian McWilliams

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April 27, 2005

Hotmail goes anonymous?

hotmail.jpgIs Microsoft's Hotmail service making it harder to track spammers?

It has come to my attention that Hotmail often does NOT include the user's Internet protocol (IP) address in outbound email messages.

I'm not sure whether this change is just a temporary, non-systemwide thing that doesn't affect all accounts. But removing this tracking information seems like a significant move backwards in trying to control spam and other abuse of Hotmail's service.

In the past, Hotmail always included the user's IP address in a header called X-Originating-IP. As spam expert John Levine noted to me, including the user's IP is a good idea for a variety of reasons. First, it gives recipients some power to track who's emailing them. Including the sender's IP also makes reporting spam and abuse much easier, and it also aids in spam filtering.

But in my (limited) testing, Hotmail now often lists its own (Microsoft) IP addresses in the X-Originating-IP spot. (Hotmail reliably seems to include the sender's IP address on emails sent to other Hotmail users.)

Has anyone else noticed this behavior by Hotmail? What do you think? (Hotmail users: please send me a test message from your Hotmail account.)

Among the major webmail providers, Google's Gmail service was previously the only one that didn't include the user's IP. Google presumably does this to protect the user's privacy. According to Levine, Google has "some whizzo scheme in the works" to stop Gmail spam.

(Thanks to Kevin Beck, editor of Run Strong, for the tip.)

[UPDATE: spamfighter J.D. Falk writes to say, "I've heard from an extremely reliable source at Hotmail that this is an artifact of some new load-balancing equipment, and they're working on changing things to return to the previous functionality. As usual, there's no implicitly evil intent involved." Whew.]

Posted by brian at April 27, 2005 10:46 AM


I just recieved an email from someone on
hotmail and it is still pointing to
hotmail/MS servers:

X-Originating-IP: [] =
[ bay108-nat1.bay108.hotmail.com ]

So here it is, July 20 and they are still
working on it??

Posted by: Jon at July 20, 2005 11:44 PM

Same thing on August 10th...

The load balancing is right and MS is working on it but there is no ETR as of yet.

Received: from bay102-f7.bay102.hotmail.com (HELO hotmail.com) ([])
by toip1.bellnexxia.net with ESMTP; 10 Aug 2005 12:38:22 -0400
Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC;
Wed, 10 Aug 2005 09:38:21 -0700
Received: from by by102fd.bay102.hotmail.msn.com with HTTP;
Wed, 10 Aug 2005 16:38:21 GMT
X-Originating-IP: []

Posted by: DREXX at August 10, 2005 1:36 PM

Same thing as of Sept 8 2005...

Brian said earlier:
(Hotmail reliably seems to include the sender's IP address on emails sent to other Hotmail users.)

Not true, Got several emails from a single hotmail user that all have HOTMAIL X-Orginatiing-IPs. Trying to solve a harassing emailer, but thanx to this stupidity, I can't track him.

Received: from hotmail.com ([]) by mc12-f3.hotmail.com with Microsoft SMTPSVC(6.0.3790.211);
Tue, 6 Sep 2005 13:42:11 -0700
Received: from mail pickup service by hotmail.com with Microsoft SMTPSVC;
Tue, 6 Sep 2005 13:42:11 -0700
Received: from by by106fd.bay106.hotmail.msn.com with HTTP;
Tue, 06 Sep 2005 20:42:10 GMT
X-Originating-IP: []

Posted by: Matt at September 8, 2005 7:48 AM

watch your back Suha Azar, what goes aorund comes around (Your time will come).

Posted by: at October 2, 2005 12:51 AM

Posted by: Mark Odell at December 1, 2005 11:20 PM


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