Problem with Two Exchange Servers Communicating With One Another from Separate Networks

Posted on 2006-11-09
Last Modified: 2010-03-06

I have two Exchange 2003 servers, one master and one member.  They're on separate networks.

For example, ex01 is in and ex02 is in  If I was a machine in, I would be able to communicate to the port 25 of ex01 with no problems:

220 ex01 Microsoft ESMTP MAIL Service at ....

For some reason, when I try to communicate on the SMTP port 25 from going to ex01, I get:

220 *******************************

And any input results in Unrecognized command.

I suspect it has to do with relaying but for testing purposes I've set the SMTP to 'Allow all except below' with the list being empty on both servers.  And yet I still get the same error.

How can I isolate the issue?


Question by:popneil
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Assisted Solution

robjeeves earned 100 total points
ID: 17911950
What router is linking these servers? Sounds like Cicso to me running the SMTP FIXUP command?

Do you have Cisco between the two Exchange boxes?

LVL 39

Accepted Solution

redseatechnologies earned 150 total points
ID: 17912285
Hi popneil,

Roberto is correct - that is the Pix SMTP Fixup

Unfortunately, the MS KB Article on this is dead, and there is nothing else out there that looks useful (or at least, as useful as that link was)

Here is what we can give you;


Hope that helps,


Author Comment

ID: 17912583
That was indeed correct.

I was surprised as the latest PIX would have support for ESMTP.  For now the solution is good for the situation but I may need to revisit the inspection map again.

Thanks again.

Expert Comment

ID: 17913266
Glad it helped mate. Thanks for the grade too

LVL 104

Expert Comment

ID: 17923141
Annoying when MS pull useful articles.
Thankfully they cannot do anything about the archive...


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