Re: earthlink users problem

From: Trevor OE News (_at_)
Date: 09/01/04 

Date: Wed, 1 Sep 2004 16:24:02 -0500

I don't know about that, but I can confirm that we are unable to send mail to Earthlink as well and get the exact same response from them, even after multiple retry attempts. SBS2003 Premium also.

-Trevor
  "RP" <rp@nospam.com> wrote in message news:e5T6gYGkEHA.3648@TK2MSFTNGP09.phx.gbl...
  Hi all, our users were unable to email earthlink.net recipients. After contacting their tech support, they replied as follows. I want to know if it is safe to run the command they suggest for Exchange (highlighted in bold). We are running SBS03 Premium. thanks!

  The information below is of a technical nature and you may wish to forward
  this to your mailserver administrator in the event that you do not fulfill
  that role yourself.

  Our engineers have informed us that the error you are receiving:

  550-EarthLink does not recognize your computer ([IP]) as connecting from
  an EarthLink connection. If this is in error, please contact technical
  support.
  550-relaying to <********@earthlink.net> prohibited by administrator

  ..is due to an improper MTA configuration with the host that is
  responsible for delivering outbound mail on your network. In a nutshell,
  the mailserver 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.

  The behavior exhibited by the sending mailserver, in this case, is not
  standard. According to RFC 2821, "Address Resolution and Mail Handling":

    "If one or more MX RRs are found for a given
     name, SMTP systems MUST NOT utilize any A RRs associated with that
     name unless they are located using the MX RRs; the "implicit MX" rule
     above applies only if there are no MX records present. If MX records
     are present, but none of them are usable, this situation MUST be
     reported as an error."

  Currently the EarthLink.net mx record resolves as follows:

  mx4.earthlink.net
  mx5.earthlink.net
  mx6.earthlink.net
  mx7.earthlink.net
  mx8.earthlink.net
  mx9.earthlink.net
  mxa.earthlink.net
  mxb.earthlink.net
  mxc.earthlink.net
  mxd.earthlink.net
  mxe.earthlink.net
  mx1.earthlink.net
  mx2.earthlink.net
  mx3.earthlink.net

  You may wish to verify that you are able to successfully resolve this
  record through your nameservers, and that you can successfully route to
  these hosts.

  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=winsvr2003

  Our engineers have informed us, however, that the byte size of
  our MX record is under the 512 byte limit and is within an RFC
  compliant range. If your firewall restricts UDP packet transfers
  though, you may want to verify that it will allow transfer of a
  MX record within the size limitations specified by RFC1035:

  http://www.faqs.org/rfcs/rfc1035.html

  Microsoft Exchange users have reported to us that a Windows 2003 server
  has included Extension Mechanisms for DNS (EDNS0) to allow larger
  packets. If you run this command on a 2003 server: "dnscmd Server
  Name/Config /EnableEDnsProbes 0", it fixes it without making any changes
  to the firewall.

  Assuming that the earthlink.net MX is resolvable, however, our
  engineers have informed us that if the sending mailserver cannot
  immediately establish a connection to deliver the intended e-mail, the
  MTA should attempt to retry a connection to the EarthLink MX, rather
  than defaulting to the earthlink.net 'A' record or smtp.earthlink.net.
  If, upon review of your mail, you believe that your report
  should be personally reviewed by an Abuse staff member,
  please reply to this message. Include this entire text and
  your original message located below. When resubmitting
  reports, please include a brief explanation as to why
  resubmission was necessary. When we receive your
  resubmission with this message included, we'll investigate
  the matter and use it to further refine our filters.

Relevant Pages

  • Re: earthlink users problem
    ... receiving SMTP mail directly into your Exchange Server ... Do some of your users have Earthlink personal accounts and have set that up ... this to your mailserver administrator in the event that you do not fulfill ... delivery attempts through the 'A' record will consequently fail ...
    (microsoft.public.windows.server.sbs)
  • Re: Exchange
    ... You can create another SMTP connector for the earthlink domain and let it go ... > 17.248) as connecting from an EarthLink connection. ... > Abuse Details: ... >> the mailserver which attempted to deliver mail to the earthlink.net ...
    (microsoft.public.windows.server.sbs)
  • Re: Exchange
    ... want all mail being sent to Earthlink email addresses to go thru this 2nd ... >>> 17.248) as connecting from an EarthLink connection. ... >>> Abuse Details: ... >>>> the mailserver which attempted to deliver mail to the earthlink.net ...
    (microsoft.public.windows.server.sbs)
  • Re: earthlink users problem
    ... Do some of your users have Earthlink personal accounts and have set that up as an additional email account in either outlook or outlook express??? ... this to your mailserver administrator in the event that you do not fulfill ... immediately establish a connection to deliver the intended e-mail, ... If, upon review of your mail, you believe that your report ...
    (microsoft.public.windows.server.sbs)
  • Re: earthlink users problem
    ... only earthlink seems to be an issue and from reading their reply it seems ... > The behavior exhibited by the sending mailserver, in this case, is not ... > immediately establish a connection to deliver the intended e-mail, ... > If, upon review of your mail, you believe that your report ...
    (microsoft.public.windows.server.sbs)