Can't send mail to one email server which is on my DMZ

I can telnet to the other email servers port. I can resolve the address. All mail to the domain is left in the queue.

Did you checked if the appropriate ports are open? on the server or no firewall?

I can telnet to port 25 on the remote server..

The following ports are also open IMAP3 + 4, SMTP, POP, HTTP

can you remove the server temporarily from the DMZ zone and test if this will work?

Sorry no. The DMZ server is acting as a forwarding server for email.

Ok, in that case try to use a packet listener to see where is the problem and why the emails are not reaching the server?

Done that. I can allow all packets through (LAN -> DMZ) and nothing. I'm not an expert on DNS and I'm leaning DNS. Any thoughts?

can you do connection by ip address?

I'm reading about bypassing DNS using exchange SMTP connectors. Any

What do you mean by your last question?

I mean use the mail server ip number instead of its DNS name? will that work, if yes we will see how to solve that DNS problem

Can you provide technical directions unless you are referring to telneting to port 25 via address or IP please?

Both IP and DNS resolve using telnet to port 25

I don't think that it is a DNS problem, the server is not seeing the packets for a reason, hmm we need more testing again on the server, did you tried to restart the services related ?

Yes. Several times.

http://www.computerperformance.co.uk/exchange2003/exchange2003_logs_diagnostic.htm#Instructions%20on%20how%20to%20turn%20on%20Diagnostic%20Logging

They propose the Solar wind Exchange monitor,
any diagnostic tool could be helpful

Installed. Now what? Everything looks fine.

can you see anything in the logs?
any thing coming to the server and dropped there?

Nothing arriving at the server. Exchange has the domain in the retry queue for all messages.

I need to leave for tonight.

Man I believe that the network is ok now but your server is unresponsive :(

The server is up again. I'm trying to migrate as soon as possible; however, this one routing issue is preventing me from moving forward.

I increased the points. Any exchange and routing people out there? I can send emails to all domains except the one on my DMZ; however, I can telnet to the computer on the DMZ.

mgonullu:

Any ideas?

sorry man for not able to logon during the day give me a while I will try to investigate

Hey friend, what are you using for DMZ?

My corporate firewall separates lan, wan and dmz. The error in exchange that I keep getting is "unable to bind to the destination server in DNS"

Hey Friend, what about this EE post:
https://www.experts-exchange.com/questions/22110833/Unable-to-bind-the-destination-server-in-DNS.html

https://www.experts-exchange.com/questions/21166568/Unable-to-bind-to-the-destination-server-in-DNS.html

I'm not a DNS guy.

Do I need to add a mx record to the forward lookup of the destination I'm having trouble connecting to?

Can I test this on a personal computer using the host file, lmhost file or something similar prior to implementing in our organization?

I don't believe it. I think it's working!!!

Awesome! It works!

good