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NDR

It seems that we cannot send messages to a particular domain. We can however receive them.
They say that their domain is not blocking us at all but I can send to the user from a yahoo account that I have.
I'm running Exchange 2000 on a clustered windows 2000 server, sp1.
When I look at the badmail dir...It says that Im getting specific error 0xc00402c7. I cannot find this error in Technet.
Also, when the user gets an NDR, it has code 4.4.7 on it which I found that says it is probably on the receiving end. Can I rule out everything on my end, that is, the configuration with my server? Thanks!!!
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jensavoia
Asked:
jensavoia
1 Solution
 
andyalderSaggar makers bottom knockerCommented:
Can you paste the NDR in here so we can see the full text of the message please, change domain names and IP addresses if you want to ensure privacy.
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jensavoiaAuthor Commented:
Thanks!!! Here you go...

Your message did not reach some or all of the intended recipients.

      Subject:     test
      Sent:     6/29/01 3:31 PM

The following recipient(s) could not be reached:

      Mike.Smith@xyz.com on 7/1/01 3:40 PM
            Could not deliver the message in the time limit specified.  Please retry or contact your administrator.
            <server.local.domain #4.4.7>
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andyalderSaggar makers bottom knockerCommented:
Hmm, just a local NDR rather than one from the recieving server. Suggests that they have a firewall that does not give meaningful error messages and does not return it's own NDRs.

Is there a PTR record for your mailserver's IP address? (or your router if you use NAT a PTR for this). Often missing PTR causes problems sending mail to strict firewalls.

Are you relaying through an ISP's mailserver or sending direct through DNS lookups?

Finally if you start a cmd session on your mailserver can you run nslookup and check their MX record and then telnet to this address on port 25 OK?
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jensavoiaAuthor Commented:
Yes, there is a PTR record for my mailserver's IP Address on our local DNS server. We are behind a firewall, and do go through an ISP's server for resolution on the Internet.
I opened a cmd session, and could not resolve with nslookup and also could not telnet into their server. It said connect failed. Thanks for your help!
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jensavoiaAuthor Commented:
Yes, there is a PTR record for my mailserver's IP Address on our local DNS server. We are behind a firewall, and do go through an ISP's server for resolution on the Internet.
I opened a cmd session, and could not resolve with nslookup and also could not telnet into their server. It said connect failed. Thanks for your help!
0
 
jensavoiaAuthor Commented:
Yes, there is a PTR record for my mailserver's IP Address on our local DNS server. We are behind a firewall, and do go through an ISP's server for resolution on the Internet.
I opened a cmd session, and could not resolve with nslookup and also could not telnet into their server. It said connect failed. Thanks for your help!
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andyalderSaggar makers bottom knockerCommented:
You're behind your own firewall so chances are that you send all mail to firewall and it relays it on to the Internet. NSlookup and telnet on 25 failing can be expected in this case.

There might be something in the firewall's logs telling why delivery failed.
Having a local PTR for your mailserver is unimportant. You need to check there is a PTR for the public IP address(es) of your firewall that can be resolved from the Internet.

go to www.samspade.org and enter the IP address of your firewall in the very bottom box of the page and hit the query DNS button to get them to do the lookup for you as you will get fake/private records from internal DNS server if you do the nslookup yourself.
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bruintjeCommented:
Hello jensavoia@idg

this question is open for more then 2 months
time to clean up
if not stated otherwise

my recom will be
-PAQ
-points to andyalder
-this will be finalized by an EE Moderator
-with no further update (15.09.2002)

PLEASE DO NOT ACCEPT THIS COMMENT AS ANSWER

HAGD:O)Bruintje
posted by ToolzEE v1.0
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JgouldCommented:
Question has been closed as per recommendation

JGould-EE Moderator
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