Another annoying MS Exchange problem !!!

[BassAddict]

Ok, someones moaned that an address no longer works - unfortunatly it was setup before I worked here so I dont know how it worked originally !
They have a DL with one member, the DL has external address of "marketing@domain.co.uk"
The only member of the DL is a custom recipient (sorry, "contact" as its now called :) ) which points to a Unix box running oracle CRM (apparently!) - so this address, I'm told, is marketing.mails@servername.uk.internal-domain.net
When you send to it, you get an NDR saying the "destination server could not be found in dns".
I changed the logging on the exchange server and got it give me an NDR error code, which I then found means:
Numeric Code: 5.4.0

First Available: Exchange 2000 Service Pack 1

Possible Causes:• An authoritative host was not found in DNS.
• The smarthost entry is incorrect.
• FQDN name in HOSTS file. This issue was fixed in Windows 2000 Service Pack 3 (SP3).
• There was a DNS failure or you constructed an invalid IP address for your smarthost. *
• SMTP VS does not have a valid FQDN, or your SMTP VS FQDN lookup failed.
• A contact's SMTP domain does not resolve to any SMTP address spaces.
Troubleshooting: Use Nslookup to check the DNS. Verify that the IP address is in IPv4 literal format. Verify that there is a valid DNS entry for the server or computer name in question. If you are relying on the FQDN in HOSTS file, ignore it and update the entry in Exchange System Manager with valid IP address or correct name.

Any idea what the smegg that means ?!!!! From the server that generates the NDR you can telnet to port 25 of the destination server (connecting via either just the servername or servername.uk.internal-domain.net
Any suggestions ?!!!
Ta :)
Rich

[ChadH]

Using the command nslookup, check out the MX records for that domain name - preferably do it from the exchange server.

Just in case you don't know after running the command type:
set type=mx
then type in 'servername.uk.internal-domain.net' (I assume that this is just a generic version of the domain name)

You should get a response telling you which mail servers are responsible with dealing with mail to that domain. If you don't, then you will need to create an MX record in DNS for that domain. If this is just used internally then you can create it on your internal DNS servers. If it's used externally, then you will need to add the record to the public DNS server that is responsible for that domain.

Hope that helps.

Chad

[BassAddict]

Yeah - nslookup all worked ok, also could also telnet to port 25 from the exchange box to the unix box, although the characters were all wrong - didn't think anything of this at the time until running telnet from my a machine not behind the firewall.
Raised it with comms to check before I left so hopfully it'll be working in the morn :) Cheers for the tips though :)
Rich

[BassAddict]

Well, still not working ! Bugger !
From my PC - I can telnet to port 25 of the unix host and get this :
"220 uk-sol-007-f04.uk.mytravelgroup.net ESMTP Sendmail 8.11.7p1+Sun/8.11.6; Thu, 25 Nov 2004 11:29:41 GMT "

From the the mailserver sending the NDR, you get this :
"220 *******00***0************************************* **************************2******200*******0*****"

Same number of characters, it looks like the same message, but only the zero's and two's get displayed ???!
Any idea's where I should look next ?!! Ta very much !
Rich