Re: MX failure - going to A record

"Robert Harker" <harker@xxxxxxxxxx> writes:

Humm... I wonder if this is a problem with a broken Micro$oft DNS
server.

Well. I'm not using any Microsoft products. But others who see the same
error might be. My firewall may also be responsible.
I can get the MX records fine, however.

Here's the response from Earthlink.

--------------------------
The error message is due to an improper MTA configuration with the host that
is responsible for delivering outbound mail on your network. In a nutshell,
the mail server which attempted to deliver mail to the earthlink.net e-mail
address was initially unable to successfully deliver the mail to the
earthlink.net MX (more than likely due to high load on our end; no EarthLink
MX host was available to accept the transaction at the moment of the
delivery attempt), and so the EarthLink 'A' record was attempted by the
sending mailserver. The earthlink.net 'A' record, however, forwards port 25
connections to our outbound SMTP servers. Unless the mailserver attempting
the transaction maintains IP connectivity through the EarthLink network,
delivery attempts through the 'A' record will consequently fail and the
above quoted error message will be returned.
It has been reported that some mailservers behind firewalls which do not
allow transfer of UDP packets larger than 512 bytes may not be able to
return the MX record for earthlink.net.

For more information, please see:
http://support.microsoft.com/default.aspx?scid=kb;en-us;828263&Product=winsv
r2003
-------------

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