We help IT Professionals succeed at work.

Exchange 2003 routing group problem

2good2 asked
Last Modified: 2008-01-09
I have the following situation.

Two Exchange 2003 Servers in one AD with two subnets (seperate locations) linked by VPN.

Server A: email @a.com and @b.com
Server B: email @c.com

Administrative group with two routing groups, each with a SMTP connector and a Routing Group connector. Each server has two SMTP connectors: port 25 and port 26. Port 26 is used for external e-mail: the cisco router maps port 25 (external) to port 26 internal so that smtp communiction (over port 25) between the two servers is possible.

Everything worked fine until somehow something was changed: internal e-mail between site A and site B isn't possible anymore! (delivery status notfication e-mails)

Hope someone can help me to fix this problem.

Thanks in advance!
Watch Question

Email communication between exchange servers works via SMTP.

try to telnet the other server and see if you get the banner.  (either on port 25 or 26) accournding to your setup.

if you cannot telnet, look into the firewall & router.

Let me know what you find.


telnet on port 25 works fine on both servers.


I believe you actually dropped an email via telnet right ?

Enable message tracking.

Turn up logging on transport to maximum.

Monitor the message tracking and the event logs.

See if you find s'thing there.

If you can telnet and spoof and email, then the exchange servers should be able to communicate.

Which queue are the messages stuck in ?



Users on server A can't send e-mail to users on server B and vice versa.
Telnet (port 25) from server A to B and from B to A is working without any problem.


I enabled maximum logging but I don't see the problem of the "internal" e-mail.

Well if the mails are not making through, they must be stuck in the queue.  What queue are they stuck in ?

Under servers, look into the "Queues" in your Exchange System Manager to look at that.  What did message tracking tell you?

(let me know if you don't know about message tracking).

Also, don't just telnet , spoof a real mail:

telnet <servername> 25


mail from: <some@some.com>
rcpt to: <an internal email address you are testing@yourDomain.com>
This is a test email from telnet.

Now you should be able to get this in the inbox.

Hope this helps.


Problem was in VPN/Cisco routers..... Telnet (port 25) was working without any problem but somehow ip inspect on smtp protocol was used and that's causing some problems between Exchange Servers.

So spoofing an email should have helped u pin that down, but i'm glad its resolved.

This one is on us!
(Get your first solution completely free - no credit card required)
Unlock the solution to this question.
Join our community and discover your potential

Experts Exchange is the only place where you can interact directly with leading experts in the technology field. Become a member today and access the collective knowledge of thousands of technology experts.

*This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.


Please enter a first name

Please enter a last name

8+ characters (letters, numbers, and a symbol)

By clicking, you agree to the Terms of Use and Privacy Policy.