a buttload of 550 SMTP errors

[Alan Truism]

We are experiencing a bunch of problems with outgoing messages on our
exchange server. The problem frequently occurs when we send messages to
distribution groups that contain people external to our organization,
however I believe they occasionally occur when mail is sent directly to
the individual.

The bounce back messages come from our server (smexec-mail.kpdexech.com
in the examples below). They're mostly 550 error variations that seem
to indicate a problem with our server's SMTP communication with the
recipients mail server. Can anyone offer any suggestions?


***@blat-blat.com on 1/25/2007 8:51 AM
There was a SMTP communication problem with the recipient's email
server.
Please contact your system administrator.
<smexec-mail.kpdexech.com #5.5.0 smtp;553 sorry, that domain isn't in
my list of allowed rcpthosts (#5.7.1)>


***@wee-wee.net on 1/25/2007 9:17 AM
There was a SMTP communication problem with the recipient's email
server.
Please contact your system administrator.
<smexec-mail.kpdexech.com #5.5.0 smtp;550-fw.kpdexech.com
(smexec-mail.kpdexech.com) [70.162.120.178] is currently not>


You do not have permission to send to this recipient. For assistance,
contact your system administrator.
<smexec-mail.kpdexech.com #5.7.1 smtp;550 5.7.1 <***@jam.com>...
Relaying denied>

***@bumbler.com on 1/25/2007 9:17 AM
There was a SMTP communication problem with the recipient's email
server. Please contact your system administrator.
<smexec-mail.kpdexech.com #5.5.0 smtp;550 not local host
consumerfed.com, not a gateway>



"There was a SMTP communication problem with the recipient's email
server. Please contact your system administrator."
"You do not have permission to send to this recipient. For assistance,
contact your system administrator."

[Kevin Longley]

Is this a recent development?

Post by Alan Truism
We are experiencing a bunch of problems with outgoing messages on our
exchange server. The problem frequently occurs when we send messages to
distribution groups that contain people external to our organization,
however I believe they occasionally occur when mail is sent directly to
the individual.
The bounce back messages come from our server (smexec-mail.kpdexech.com
in the examples below). They're mostly 550 error variations that seem
to indicate a problem with our server's SMTP communication with the
recipients mail server. Can anyone offer any suggestions?
There was a SMTP communication problem with the recipient's email
server.
Please contact your system administrator.
<smexec-mail.kpdexech.com #5.5.0 smtp;553 sorry, that domain isn't in
my list of allowed rcpthosts (#5.7.1)>
There was a SMTP communication problem with the recipient's email
server.
Please contact your system administrator.
<smexec-mail.kpdexech.com #5.5.0 smtp;550-fw.kpdexech.com
(smexec-mail.kpdexech.com) [70.162.120.178] is currently not>
You do not have permission to send to this recipient. For assistance,
contact your system administrator.
Relaying denied>
There was a SMTP communication problem with the recipient's email
server. Please contact your system administrator.
<smexec-mail.kpdexech.com #5.5.0 smtp;550 not local host
consumerfed.com, not a gateway>
"There was a SMTP communication problem with the recipient's email
server. Please contact your system administrator."
"You do not have permission to send to this recipient. For assistance,
contact your system administrator."

[Alan Truism]

Post by Kevin Longley

Post by Alan Truism
We are experiencing a bunch of problems with outgoing messages on our
exchange server. The problem frequently occurs when we send messages to
distribution groups that contain people external to our organization,
however I believe they occasionally occur when mail is sent directly to
the individual.
The bounce back messages come from our server (smexec-mail.kpdexech.com
in the examples below). They're mostly 550 error variations that seem
to indicate a problem with our server's SMTP communication with the
recipients mail server. Can anyone offer any suggestions?
There was a SMTP communication problem with the recipient's email
server.
Please contact your system administrator.
<smexec-mail.kpdexech.com #5.5.0 smtp;553 sorry, that domain isn't in
my list of allowed rcpthosts (#5.7.1)>
There was a SMTP communication problem with the recipient's email
server.
Please contact your system administrator.
<smexec-mail.kpdexech.com #5.5.0 smtp;550-fw.kpdexech.com
(smexec-mail.kpdexech.com) [70.162.120.178] is currently not>
You do not have permission to send to this recipient. For assistance,
contact your system administrator.
Relaying denied>
There was a SMTP communication problem with the recipient's email
server. Please contact your system administrator.
<smexec-mail.kpdexech.com #5.5.0 smtp;550 not local host
consumerfed.com, not a gateway>
"There was a SMTP communication problem with the recipient's email
server. Please contact your system administrator."
"You do not have permission to send to this recipient. For assistance,
contact your system administrator."

Is this a recent development?

Yes, relatively speaking.

[Kevin Longley]

Does your public host name record, for your mx value, equal the host name
assigned to your smtp virtual server? Sometimes the receiving end will try
to perform a reverse lookup based upon the smtp server name in the mail
header. If they don't match you can get a relay denied ndr. It is also
possible to see these issues if there is issues with your public dns
servers.

Post by Alan Truism

Post by Kevin Longley

Post by Alan Truism
We are experiencing a bunch of problems with outgoing messages on our
exchange server. The problem frequently occurs when we send messages to
distribution groups that contain people external to our organization,
however I believe they occasionally occur when mail is sent directly to
the individual.
The bounce back messages come from our server (smexec-mail.kpdexech.com
in the examples below). They're mostly 550 error variations that seem
to indicate a problem with our server's SMTP communication with the
recipients mail server. Can anyone offer any suggestions?
There was a SMTP communication problem with the recipient's email
server.
Please contact your system administrator.
<smexec-mail.kpdexech.com #5.5.0 smtp;553 sorry, that domain isn't in
my list of allowed rcpthosts (#5.7.1)>
There was a SMTP communication problem with the recipient's email
server.
Please contact your system administrator.
<smexec-mail.kpdexech.com #5.5.0 smtp;550-fw.kpdexech.com
(smexec-mail.kpdexech.com) [70.162.120.178] is currently not>
You do not have permission to send to this recipient. For assistance,
contact your system administrator.
Relaying denied>
There was a SMTP communication problem with the recipient's email
server. Please contact your system administrator.
<smexec-mail.kpdexech.com #5.5.0 smtp;550 not local host
consumerfed.com, not a gateway>
"There was a SMTP communication problem with the recipient's email
server. Please contact your system administrator."
"You do not have permission to send to this recipient. For assistance,
contact your system administrator."

Is this a recent development?

Yes, relatively speaking.

[Rich Matheisen [MVP]]

Post by Kevin Longley
Does your public host name record, for your mx value, equal the host name
assigned to your smtp virtual server? Sometimes the receiving end will try
to perform a reverse lookup based upon the smtp server name in the mail
header.

That'd be a forward-lookup, if you're talking about checking the
EHLO/HELO address. Or are you referring the to the contents of the
"From:" (or "Sender:", etc.) header? That's probably SenderID and PRA
validation.

Post by Kevin Longley
If they don't match you can get a relay denied ndr. It is also
possible to see these issues if there is issues with your public dns
servers

Considering the number of different texts in those errors I'd be
inclined to believe that the server (or a SMTP client that's using the
server) is infected with a virus or worm. It sure looks like it's
sending e-mail for domains that the receiving servers don't handle.

I'd be checking the SMTP protocol log on smexec-mail.kpdexech.com to
see where those messages are coming from.

[Kevin Longley]

I have seen relaying denied issues when the Fqdn name, as found on the
properties of the smtp virtual server-delivery-advanced delivery do not
match the fqdn of the public mx record. It certainly doesn't explain some of
the other odd ndr's. Other than that I have also experienced relaying denied
issues when my isp changed to new dns servers and misconfigured our public
zone. Again I don't think that can explain some of the other odd ndr's, but
it is worth ruling out.

Post by Rich Matheisen [MVP]

Post by Kevin Longley
Does your public host name record, for your mx value, equal the host name
assigned to your smtp virtual server? Sometimes the receiving end will try
to perform a reverse lookup based upon the smtp server name in the mail
header.

That'd be a forward-lookup, if you're talking about checking the
EHLO/HELO address. Or are you referring the to the contents of the
"From:" (or "Sender:", etc.) header? That's probably SenderID and PRA
validation.

Post by Kevin Longley
If they don't match you can get a relay denied ndr. It is also
possible to see these issues if there is issues with your public dns
servers

Considering the number of different texts in those errors I'd be
inclined to believe that the server (or a SMTP client that's using the
server) is infected with a virus or worm. It sure looks like it's
sending e-mail for domains that the receiving servers don't handle.
I'd be checking the SMTP protocol log on smexec-mail.kpdexech.com to
see where those messages are coming from.
--
Rich Matheisen
MCSE+I, Exchange MVP
MS Exchange FAQ at http://www.swinc.com/resource/exch_faq.htm

[Rich Matheisen [MVP]]

Post by Kevin Longley
I have seen relaying denied issues when the Fqdn name, as found on the
properties of the smtp virtual server-delivery-advanced delivery do not
match the fqdn of the public mx record.

That's not an unusual condition considering the MX is resolved using
the domain name and the HELO/EHLO is /supposed/ to be either a FQDN or
address literal. If some jackass admin thinks that's the correct way
to vet inbound e-mail then they'll have a hell of a time explaining
why they reject e-mail from places like my place of employment where
the MX servers don't send any e-mail. MX resource records direct other
servers to the machines that /receive/ e-mail. They don't identify the
servers that /send/ e-mail.

Post by Kevin Longley
It certainly doesn't explain some of
the other odd ndr's. Other than that I have also experienced relaying denied
issues when my isp changed to new dns servers and misconfigured our public
zone. Again I don't think that can explain some of the other odd ndr's, but
it is worth ruling out.

The reasons given in the text portion of those status messages all
look like they refusing e-mail that's been sent to them and addresses
to domains they don't accept. If it were just one server (and one
brand of MTA) I'd guess that the guy was using his ISP as a relay
server and the ISP screwed something up. But that's not what I see.

Sure, investigate everything. It won't hurt to validate that things
are operating properly. Don't forget checking your IP address agains
DNS RBLs, too.

[Alan Truism]

On Jan 28, 7:27 pm, "Rich Matheisen [MVP]"

Post by Rich Matheisen [MVP]

Post by Kevin Longley
It certainly doesn't explain some of
the other odd ndr's. Other than that I have also experienced relaying denied
issues when my isp changed to new dns servers and misconfigured our public
zone. Again I don't think that can explain some of the other odd ndr's, but
it is worth ruling out.The reasons given in the text portion of those status messages all

look like they refusing e-mail that's been sent to them and addresses
to domains they don't accept. If it were just one server (and one
brand of MTA) I'd guess that the guy was using his ISP as a relay
server and the ISP screwed something up. But that's not what I see.
Sure, investigate everything. It won't hurt to validate that things
are operating properly. Don't forget checking your IP address agains
DNS RBLs, too.

RBL's ??

[Rich Matheisen [MVP]]

Post by Alan Truism
On Jan 28, 7:27 pm, "Rich Matheisen [MVP]"

Post by Rich Matheisen [MVP]

Post by Kevin Longley
It certainly doesn't explain some of
the other odd ndr's. Other than that I have also experienced relaying denied
issues when my isp changed to new dns servers and misconfigured our public
zone. Again I don't think that can explain some of the other odd ndr's, but
it is worth ruling out.The reasons given in the text portion of those status messages all

look like they refusing e-mail that's been sent to them and addresses
to domains they don't accept. If it were just one server (and one
brand of MTA) I'd guess that the guy was using his ISP as a relay
server and the ISP screwed something up. But that's not what I see.
Sure, investigate everything. It won't hurt to validate that things
are operating properly. Don't forget checking your IP address agains
DNS RBLs, too.

RBL's ??

RBL = Real-time Block List.

http://www.dnsstuff.com -- look in the middle column, test named "Spam
Database Lookup". Put your server's external IP address in the box and
click "Lookup".

[Alan Truism]

Post by Alan Truism
We are experiencing a bunch of problems with outgoing messages on our
exchange server. The problem frequently occurs when we send messages to
distribution groups that contain people external to our organization,
however I believe they occasionally occur when mail is sent directly to
the individual.
The bounce back messages come from our server (smexec-mail.kpdexech.com
in the examples below). They're mostly 550 error variations that seem
to indicate a problem with our server's SMTP communication with the
recipients mail server. Can anyone offer any suggestions?
There was a SMTP communication problem with the recipient's email
server.
Please contact your system administrator.
<smexec-mail.kpdexech.com #5.5.0 smtp;553 sorry, that domain isn't in
my list of allowed rcpthosts (#5.7.1)>
There was a SMTP communication problem with the recipient's email
server.
Please contact your system administrator.
<smexec-mail.kpdexech.com #5.5.0 smtp;550-fw.kpdexech.com
(smexec-mail.kpdexech.com) [70.162.120.178] is currently not>
You do not have permission to send to this recipient. For assistance,
contact your system administrator.
Relaying denied>
There was a SMTP communication problem with the recipient's email
server. Please contact your system administrator.
<smexec-mail.kpdexech.com #5.5.0 smtp;550 not local host
consumerfed.com, not a gateway>
"There was a SMTP communication problem with the recipient's email
server. Please contact your system administrator."
"You do not have permission to send to this recipient. For assistance,
contact your system administrator."

Here are the errors I'm getting on the server event log:

This is an SMTP protocol error log for virtual server ID 1, connection
#146. The remote host "192.165.240.160", responded to the SMTP command
"rcpt" with "550 <***@enews.eweek.org>: Relay access denied
". The full command sent was "RCPT TO:<***@enews.eweek.org>
". This will probably cause the connection to fail.


This is an SMTP protocol error log for virtual server ID 1, connection
#147. The remote host "10.84.44.5", responded to the SMTP command
"rcpt" with "550 Requested action not taken: mailbox unavailable or
not local ". The full command sent was "RCPT TO:<***@geo.com> ".
This will probably cause the connection to fail.

[Kevin Longley]

The second event regarding the mailbox not being available seems normal to
me. On the first error regarding relaying, was this indeed an email that you
were sending to ***@enews.eweek.org? If so I would contact them and
find out exactly why you were denied.

Post by Alan Truism

Post by Alan Truism
We are experiencing a bunch of problems with outgoing messages on our
exchange server. The problem frequently occurs when we send messages to
distribution groups that contain people external to our organization,
however I believe they occasionally occur when mail is sent directly to
the individual.
The bounce back messages come from our server (smexec-mail.kpdexech.com
in the examples below). They're mostly 550 error variations that seem
to indicate a problem with our server's SMTP communication with the
recipients mail server. Can anyone offer any suggestions?
There was a SMTP communication problem with the recipient's email
server.
Please contact your system administrator.
<smexec-mail.kpdexech.com #5.5.0 smtp;553 sorry, that domain isn't in
my list of allowed rcpthosts (#5.7.1)>
There was a SMTP communication problem with the recipient's email
server.
Please contact your system administrator.
<smexec-mail.kpdexech.com #5.5.0 smtp;550-fw.kpdexech.com
(smexec-mail.kpdexech.com) [70.162.120.178] is currently not>
You do not have permission to send to this recipient. For assistance,
contact your system administrator.
Relaying denied>
There was a SMTP communication problem with the recipient's email
server. Please contact your system administrator.
<smexec-mail.kpdexech.com #5.5.0 smtp;550 not local host
consumerfed.com, not a gateway>
"There was a SMTP communication problem with the recipient's email
server. Please contact your system administrator."
"You do not have permission to send to this recipient. For assistance,
contact your system administrator."

This is an SMTP protocol error log for virtual server ID 1, connection
#146. The remote host "192.165.240.160", responded to the SMTP command
". This will probably cause the connection to fail.
This is an SMTP protocol error log for virtual server ID 1, connection
#147. The remote host "10.84.44.5", responded to the SMTP command
"rcpt" with "550 Requested action not taken: mailbox unavailable or
This will probably cause the connection to fail.