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Unable to receive SMTP messages from outside the network.

Posted on 2005-03-12
Medium Priority
Last Modified: 2010-08-05
We have a simple setup.  One server set up as the domain controller, one firewall, and about 15 or so clients.

I am setting up a new Windows 2003 server running Exchange 2003.  I am not able to receive Emails from outside domains, but I can send them to outside domains and to others within the organization.

We have  a firewall that is running ISA 2000.  Our ISP has properly configured the MX records and is pointing the mail.REGISTEREDDOMAIN.org to the firewall.  I am able to ping our mail.REGISTEREDDOMAIN.org domain, and have checked the mx records using nslookup.  I think eveything on the ISP end is fine since everything was working with our old server (which was running Exchange 5.5).  The old server is no longer part of the network.  I've moved the user data files on the old over to the new server and have EXmerged the old 5.5 mailboxes to pst files to be imported into the new exchange box.

I've added the mx record to the server's DNS (SERVERNAME.DOMAINNAME.ORG).

I think this is a routing issue, but I'm not sure where to go from here.  I noticed on the old server that IMS was rerouting incoming SMTP messages (through IMS) to REGISTEREDDOMAIN.ORG.  How do I acheive this same functionality with the new server?  Or is there a setting on the firewall running ISA that needs to redirect to the server?

Thanks in advance for all of your help!  This website has saved my life more than once, I hope you can do it again!


Question by:thung226
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LVL 27

Expert Comment

ID: 13527525
On the ISA firewall, are you forwarding Port 25 to the Exchange server?
You need to do this.

Expert Comment

ID: 13545045
firstly try to isolate the problem..tey removing the isa server from the picture and check whether u are able to send /recieve mails from the outside world..also u got any antivirus for gateways i.e. trend micro interscan or so....and also which isa u got 2000 or 2004 and also the exchange versions

Author Comment

ID: 13545373
Thanks, I was able to figure it out.  The firewall wasn't publishing SMTP requests to the proper IP.  The old network used a different number scheme for the subnet, so incoming requests weren't being forwarded properly.  

My new problem is about OWA.  It appears that I can access OWA from within the network, but not from outside.  This may be the same issue, but I changed the DNS servers on the PDC to point to the ones from the ISP.  I'm not sure if this is the problem (I can't access network shares when connecting to the vpn), but I think I'll follow this lead and see where it takes me.  I think all of requests made to the firewall are forwarding now, but I need to take a second look and debug.

Man, if it's not one thing with this, it's another.  This is a great learning experience, but man, is it crazy.


Accepted Solution

virag earned 1185 total points
ID: 13546764

Author Comment

ID: 13557150
great; thanks.  i was able to get owa up, but the public folder won't come up through owa.  i keep getting a "403 Forbidden - The server denies the specified Uniform Resource Locator (URL)" error.


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