Email flow problem in Exchange 2003

Question

I have a problem whit some emails that are not being delivered to the user inbox. The SMTP server on the DMZ that receives email from the internet is a Symantec Brigthmail Gateway, this server reports that the message was delivered normally to the exchange server:

Screenshoot2 http://img1.uploadscreenshot.com/images/orig/11/32015524182-orig.jpg

The DMZ server forwars the incoming mail to the exchange server that is on the LAN segment, and the message tracking on the exchange server reports the email being submited to the advanced queue:

http://img1.uploadscreenshot.com/images/orig/11/32015184068-orig.jpg http://img1.uploadscreenshot.com/images/orig/11/32015505074-orig.jpg

I have done severals searches on google, without any luck.
have any one of you guys experienced similar problems?

Any help or pointers would be very appreciated.

as requested, here is a transcript of a smtp session:

---

helo
250 mail2.XXXXXXXXXXXXXXXX.XXX.XX Hello [192.168.9.6]
MAIL FROM: tita.lee@AAAAAAAAAAAAAAA.AAA.AA
RCPT TO: juan.peres@XXXXXXXXXXXXXXXX.XXX.XX
DATA
Subject: Mensaje de Prueba

Test
.

250 2.1.0 tita.lee@AAAAAAAAAAAAAAA.AAA.AA....Sender OK  
250 2.1.5 juan.peres@XXXXXXXXXXXXXXXX.XXX.XX  
354 Start mail input; end with <CRLF>.<CRLF>  
250 2.6.0 <'SSCZMAIL01YNJDhaH5L0000003c@mail2.XXXXXXXXXXXXXXXX.XXX.XX> Queued mail for
 delivery

Answer 1

You can try mimicking the session between the Symantec box and the Exchange server to see if you can get a useful error message. It's possible your Exchange server is locked down to only talk to the Symantec box, so you may have to add your IP address to the allowed IP list.

Open up a command prompt and type the following. Replace anything I put in <angle brackets> with the values from a message which is being rejected. For each new line below, press Enter and give it a second to send a response.

HELO symantec-gateway
telnet <Your Exchange Server> 25
MAIL FROM: <Sender Address>
RCPT TO: <Recipient Address>
DATA
Subject: <Message Subject>

Test
.

The new line between the subject and the test message is intentional and required, and that is a period (.) on its own on the last line - that's important. When you do that, you should get a message from the Exchange Server with something like Message 123abc@exchange.acme-widgets.com successfully queued for delivery. You can then type quit and you should be dropped back to a command line.

Please update your original post to include any errors you receive.

Edit

You could try turning up the diagnostic logging to see if you get anything useful.
Open up Exchange System Manager and go down to Administrative Groups => (Your Administrative Group => Servers => (Your Server) and right click on it. Go to Properties and go to the Diagnostics Logging tab.

Under the Services on the left, choose MSExchangeTransport and turn NDR and SMTP Protocol up to Medium.

Hopefully this will log (in the Application Event Log) all NDR messages sent, along with their status codes. When you get some logs, update your question with them. Also, when you get some useful logs, turn the diagnostic logging back down again - your server will love you for it!