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akhalighiFlag for Canada

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exchange 2010 and 2003 mail flow problems

I have exchange 2010 co-existing with 2003  - no errors through the install and I see all legacy mail boxes.

I just migrated one mailbox to 2010 ; this mailbox is unable to send/receive any emails.

My plan is to keep exchange 2003 handling all email send/receives until we can move all users to 2010 system.

I configured a bi-directional routing group between 2003 and 2010 ; then I was able to receive email on mailbox that is moved to 2010.

To be able to send emails ; I created a send connector on 2010 that sends emails through 2003 exchange (as it's smart relay) and mailbox 2010 was able to send emails too.

Then I noticed that flow of the email between 2003 and 2010 mailboxes is affected ; I saw some internal loop messages on 2010 queue viewer.  2003 mail boxes were sending emails using send connector on 2010 ! and send connector on 2010 was using 2003 exchange as relay !

So .. I removed bi-directional loop and restarted 2003 exchange , back to square one. any suggestions will be greatly appreciated . should I just create a one way routing ? from 2010 to 2003 ?if yes , how 2003 mailboxes can communicate with 2010 ?

here is what I need :
2010 mailboxes able to send/receive email to 2003 and Internet
2003 mailboxes able to send/receive emails ro 2010 and Internet
able to replicate public folders from 2003 to 2010 and keep them Synced
2003 server should remain main gateway for send/receive emails for the time.
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This is probably because the default SMTP Vrtual Server has got a smarthost configured.

Please see my guide here on how to resolve this:
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Hi Busbar , thanks ... I responded on Technet too :) I document it here as well :

I set bidirectional RGC using this command ;

 New-RoutingGroupConnector -Name "Interop RGC" -SourceTransportServers "JMBNKTIDCEXC01.Jameson.local" -TargetTransportServers "151-tor-s.Jameson.local" -Cost 100 -Bidirectional $true -PublicFolderReferralsEnabled $true

after setting this route , 2010 mail box is able to receive emails but it won't send any , Here is the command that I use to make the bidirectional connection :
in queue viewer it logs an error complaining about No connector to send email to external users..

My 2010 exchange doesn't have access to Internet ; so that I need to forward emails to a smart host ; the only smart host that I have is 2003 exchange server itself.
Once I do that ; 2010 mailbox can send emails but I see some intrenal loop errors in queue viewer ... strange thing is that I also see 2003 mailboxes coming to 2010 queue for sending emails ...

do I need to give smtp / DNS access to Internet on exchange 2010 ?

This will cause a loop.  Can you not set the 2010 server with Internet access.

When co-existing you should setup a new send connector for Internet mail, exchange 2003 will use this as well.  Using the 2003 server as a smarthost for the 2010 server will give the exact results you are seeing.

So ... this tells me that 2003 cannot handle sending emails while co-existing ? I cannot change MX-records to 2010 box for some time ... the whole reason of co-existing setup for me was to have 2003 handling normal mail flow until all mailboxes /public folders are moved to 2010 ; BES , forfront are tested and installed
etc ...

My current send connector on 2010 is not Internt type , it's Internal type and it goes through smart host (exchange 2003).
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Hi demazter , Thanks for your help...

I have a test lab where a 2007 and a 2003 co-exist ; in this enviornment mailboxes between 2007 and 2003 can communicate with each other without needing any extra send connector. but for 2007 mailboxes to be able to send emails to Internet ; I had to create a send connector on 2003 exchange server. (with 2003 as source server) :
this send connector can be seen in 2007 hub transport (organization) .attached the screenshot.

If I delete this connector , still 2007-2003 internal mail works but internet emails are unable to send to Internet. I recreated the connector and it works fine.

In my 2010 - 2003 co-existting production enviornment ; there are two issues ;

1- 2010 mailboxes cannot send emails to 2003 mailboxes internaly. (2003 can send to 2010 )

2- for every send request (internal or external) they try accessing a connector : "A matching connector cannot be found to route the external recipient"

I tried the same setup (like dev enviornment) and created a send connector under 2003 exchange , it's showing up under 2010 transport but under "source" it doesn't show 2003 server as the source ...

Have you checked the properties of the Default SMTP Virtual Server as per my very first post.

If you have a smarthost configured here it is never going to work.
No there is no smart hosts here or anywhere else.
I would remnant setting up the mailflow as I have suggested above.

This is the correct way to set it up.  If it still fails after you have configured it correctly the we can look in to it further.
Hi Demazter

I just checked that article and followed all of the steps , SMTP port is 25 across the board , no TLN at all and there is no smart host in the enviornmnet anywhere.

emails from 2010 doesn't go to 2003 even internally . it receives mail though . it looks like that my bi directional route doesn't work properly . flow of email from 2003 to 2010 is fine but from 2010 nothing goes out either to 2003 or Internet...

I don't see 2003 database anywhere in 2010 EMC but I see it from 2003 management Console, once I migrate a legacy user ; it cannot be migrated back to 2003 ...

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I will try and let you know . Yes emails stay in the queue ; for internal emails ; there is no errors but emails for outside have an error message ( there is no connector).
- Telnet wokrs fine to both port 25 and 691 from 2010 to 2k3
- I enabled maximum logging for transport services and exchange transport. anything specific you want to look for ?
somthing that I noticed .. telnet responds but not from my 2k3 server ; it's a PIX firewall between two exchange servers and that basically responds to Telnet . I think mail guard is enabled on that ..
It was the PIX firewall that was causing this issue ; here is the MS article about it :

Thanks for all of your helps.
Thanks folks , you are awsome