Internal Mail Delivery - Optimal DNS and SMTP Connector Configuration


I have inherited an Exchange 2000 server (on Windows 2000) and have not seen this issue before.  Actually, it is probably not an issue but the way it has been setup!

So the current confgiuration/situation is:

- SMTP connector that routes * to
- DNS - one MX record that points to (MX preference 5)
- is not Exchange, it is a separate postfix server.
- All service packs and updates are installed for Windows and Exchange
- Forest Functional Level is Windows 2000
- Domain Functional Level is Windows 2000 native

My problem is that all internal mail is sent to the smtp server rather than Exchange just delivering to local mailboxes.  So when we had a DNS issue yesterday, internal mail was sitting on the SMTP server for hours before being delivered...

I am looking for help in ensuring I have Exchange and the MX records setup correctly for optimal operation.......I will also be installing a new Exchange 2003 server soon so we will soon have an Exchange 2000 and an Exchange 2003 server.  The 2000 server will eventually be decommissioned and then rebuilt with 2003 so we will then have two 2003 servers.  I have already ran the forest  and domain prep.

any help and direction on this will be greatly appreciated
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SembeeConnect With a Mentor Commented:
You should not have MAPI and SMTP connections in Outlook. It should be one or the other.
Ideally you should have everything pointing at the Exchange server and if they want to retain the postfix box that should be used as a gateway server only.

You shouldn't need to restart the IS to get a change on the SMTP VS to take. I would look at message tracking to see what Exchange is actually doing with the messages. The setup is certainly a little odd, so there may be something else lurking inside the Exchange configuration - such as a custom event sink or a configuration in a third party application that is changing the behaviour of the email.

You need to sort out as many quirks as you can, before introducing the Exchange 2003 server. Exchange uses SMTP to send inter-server traffic, and if that traffic is being diverted elsewhere it will cause problems with the migration.

The first thing I would check is whether there is a smart host on the SMTP virtual server.

ESM, Servers, <your server>, Protocols, SMTP. Right click on the default SMTP VS and choose Properties. Click on the tab Delivery and then Advanced. Ensure that smart host is blank.

How are the clients configured? For Exchange for SMTP/POP3? It shouldn't be possible to send internal email via another server - that is something that has been asked for and is new to Exchange 2007.

glennbrown2Author Commented:
Hi Simon

There was an entry in the smarthost ( but i removed it last week.  I guess I need to restart the IS for it to take affect??  I restarted SMTP at the time.
I know the linux and mac users have set for the SMTP server so they can be changed to Exchange i guess

All other clients are mapi/smtp connections through outlook

glennbrown2Author Commented:
yes they are MAPI not SMP conenctions, sorry.  the problem was found to be only the MAc's and Linux boxes that are pointing to the smtp server.  Anyway, the postfix box was rebooted and that seemed to clear out old DNS entries it had
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