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I am having an outbound email issue during the Exch 03 migration. Basically, we are migrating Exch03 to new hardware, both servers are Server 03 based.

Everything runs smooth while setting up and installing Exch 03 on the new box. Public folders are all replicated. My issues are shown below....

1) After starting to move users' mailboxes to new Exch 03, they receive some undeliverable mail and bounced back mail from some vendors, then I move few users back to test around, they have no problem at all after moving back to old Exch 03.

2) Another issue is our company has Blackberry users, we don't have BES. Under each user's mailboxes, we have forward rule setup, so that both user inbox and BB can receive email. User who is moved to the new Exch 03 server, they can only send email to the BB user's inbox, mail cannot be forwarded to BB at all, smtp queue stacks up and keep trying until the time is expired.

Since not all emails that the users send out from the new Exch have problem, I am not able to narrow down what is the issue here. Can anyone give me some ideas? Could this be MX record / Reversed DNS relate? Or firewall NAT rule setting? Thanks.

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You need to elaborate about what these "bounces" are that you're receiving. Bounce messages are there to tell you things and should be read! It sounds like you're probably not NAT'ting outbound SMTP from the new Exchange Server machine the same way you were for the old machine.

In the very short term, you can probably add an SMTP Connector to your routing group with the bridgehead server specified on the connector set to the Default SMTP Virtual Server on the old Exchange Server computer and you'll probably see oubound mail delivery begin to work properly for users homed on either machine (assuming you haven't gone in and played around w/ the Default SMTP Virtual Server's settings massively on that machine).

It sounds like all you've got is pooched-up outbound SMTP delivery, to me.

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My first guess would be that you've not correctly setup forward/reverse DNS and/or the NAT on the firewall that your new server uses.

I would agree with Evan that we probably need some more information to be useful. Are you logging the outbound conversations or can you capture a few packets to help deduce what the actual error messages for the failed messages are?

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My bet is that your old exchange server has a smart host (relay server for smtp mail going outside your own organization) while your new one does not.

A typical problem is remote smtp servers denying any connection from your new exchange server if you don't have your own static external IP (with a proper PTR set), like in a dynamic ADSL IP pool or similar.

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The right place to configure a smart host is on an SMTP connector, though, and not the SMTP virtual server. A smart host setting on a virtual server is used for all mail delivery (including intra-organization delivery-- between Exchange Server computers, for example), but a smart host specified on an SMTP connector is only used for delivery via the connector. – Evan Anderson Dec 1 '09 at 3:40

Thanks for all your reply. The problem has been resolved. There is no smarthost setup, nor incorrect setting on the NAT/DNS. We have found that the public IP address that the new server using is being blocked by PBL. Since Blackberry Biz has this issue link text

So we demand to remove our IP from the PBL list. This is also the reason why some emails can be sent out and some are not, especially those forward to Blackberry.


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