IIS and SMTP - Unusual Delivery Failure Notifications

Author

Unusual Delivery Failure Notifications

Jim P. Barber

2004-01-24, 2:04 am

Hi,

I have an iis 5 smtp server that is relaying mail on our
dmz.

The server works well for the most part however I am
getting these strange delivery failures for valid
addresses like below:

This is an automatically generated Delivery Status
Notification.

Unable to deliver message to the following recipients, due
to being unable to connect successfully to the destination
mail server.

validuser+AEA-validdomain.net

-- NextPart --
Unknown MIME type: message/delivery-status

Now I did reduce these by adding my FQDN to both the
Masquerade domain and the FQDN fields of the advanced
options on the delivery tab for the server.

However I am still getting these failures. Any Ideas
would be appreciated.

Jim Barber

=?Utf-8?B?VG9ueSBTdQ==?=

2004-01-24, 2:05 am

Blacklisted?
Using a dynamic IP so a reverse lookup fails?

Tony Su

Jim P. Barber

2004-01-24, 2:05 am

Nope, I have a static IP assigned to the server w/valid
dns mx records. It has got to be some kind of
misconfiguration, but I am having trouble tracking it down.

quote:

>-----Original Message-----
>Blacklisted?
>Using a dynamic IP so a reverse lookup fails?
>
>Tony Su
>.
>

Matt Keener

2004-01-24, 2:05 am

I had (am having still, perhaps) a similar problem. Does
this server have multiple NICs? If so, move the Internet-
facing NIC to the top of the binding order (this worked
for me) (Q296893). Also check to see if you have any 3rd
party programs binding to port 25 with their own self-
contained SMTP server (eg anti-virus programs)
(Q322023)... you may have problems with SMTP socket
pooling.

quote:

>-----Original Message-----
>Nope, I have a static IP assigned to the server w/valid
>dns mx records. It has got to be some kind of
>misconfiguration, but I am having trouble tracking it

down.

quote:

>
>.
>