Is Hotmail in the habit of ignoring MX records?

Mark Foster blakjak at
Thu Jul 26 10:32:05 UTC 2012

On 26/07/12 20:35, Lou Katz wrote:
> On Thu, Jul 26, 2012 at 02:38:31AM -0500, Jimmy Hess wrote:
>> On 7/26/12, Lou Katz <lou at> wrote:
>>> One of my users has reported incoming mail failures, which I finally
>>> tracked down. It turned out that Hotmail has seen fit to send the mail
>>> to his domain's A record machine, despite the fact that he has valid MX
>>> records.
>> You looked in the mail headers and saw hotmail's mail server do that,
>> or the From address/return path just happens to be hotmail?
>> I would ask for a specific example of a domain name in which that
>> seems to happen, and  exact DNS zone contents.
>> I am sure that Hotmail does not  ignore MX in general,  unless they

No, they do.  The exact same thing has happened to me - twice, with two
seperate scenarios being fundamentally similar.  The MX is ignored, the
non-host A record is tried, if it accepts connections on Port 25 it uses
this instead.
This behavior forced me to set up the mail server on the same box as a
webserver I administer to act as a secondary MX for another domain I
administer (mail is elsewhere), in one case.
In the other, I had to simply write off the option of having
http://domain working, and live with just http://www.domain, due to the
use of a third party web host that also had an MTA on their machine that
was rejecting my email.

Like all the behemoth service providers, it's impossible to find someone
useful to talk to about these things.  I posted on Mailop about it a few
months ago, but it's not new behavior - the first instance I came across
was more than 2 years ago.


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