Re: Suddenly mails sent by IIS stop being delivered to hotmail accounts

I'm sorry about obfuscating IP and hostname, I thought it could be
resolved without leaving them visible....

No, not when published involves the relationship between published
forward and reverse DNS records, their public reputations, and your
local config.

But you are still hiding your data.

Hower that may be, your help was really useful!

Good to hear.

The PTR-HELO-A roundtrip was somewhat not perfect: the PTR resolved
the top level domain and not the FQDM of HELO the HELO FQDN was not
in A record but in CNAME.

OK, good fixup. (Technically, the matching CNAME is acceptable there,
but it creates more DNS traffic and there should be no reason to not
use an A. The idea, as you may now know, is that what the machine says
about itself is corroborated on both sides of the public DNS.)

The last thing that should solve the Junk problem could be the
Header added by IIS SMTP server "Received: from mail pickup service"
for mails saved to pickup dir.

From test run on SpamAssasin that header could generate the
UNPARSEABLE_RELAY test match...
Unfortunately seems that the implied header could not be removed...

That is a non-RFC header, but can you prove that mail that is
submitted using SMTP doesn't have the same delivery issues as that
submitted through \Pickup? One low-scored SA rule is unlikely to make
a difference.

Please provide your domain, source IP, and HELO data this time around
so it may be analyzed.

--Sandy


------------------------------------
Sanford Whiteman, Chief Technologist
Broadleaf Systems, a division of
Cypress Integrated Systems, Inc.
------------------------------------
.

Relevant Pages

  • Re: SMTP Virtual Server Quit problem
    ... will bog down if someone tries to send an attachment over 10mb....with esmtp, ... As for Helo rather than Ehlo, doesn't the server revert back to helo if ehlo ... >> The SMTP server is not performing a DNS Blacklist check of any kind. ... >> I only get a single line stating 'Quit' for the dropped connection. ...
    (microsoft.public.exchange.connectivity)
  • Re: Does this mean reverse DNS was not setup?
    ... If you've got mis-matched HELO ... You should be aware that most email transmissions are 'tested' for dns during the attempted delivery, and mail server programs routinely test all domain names found in the email headers so you may want double-check the dns for each domain name that will be passed in an email header. ... Having the domain name that is declared in the HELO statement resolve correctly now as you say is great as not not resolving is a common reason for terminating the attempted email delivery. ... if you have a failover / backup email server then the same config issues are going to apply. ...
    (microsoft.public.win2000.dns)
  • Re: Exchange 2003 messages not leaving queue
    ... AOL and RR require reverse DNS records. ... > This is an automatically generated Delivery Status Notification. ... > I looked for problems in the mail queues and have found these messages. ...
    (microsoft.public.exchange.admin)
  • Could not deliver the message in the time limit specified.
    ... destination server in DNS". ... The option to use HELO instead of EHLO is not ...
    (microsoft.public.exchange2000.general)
Loading