Public Folder Replication Issue between Exchange 2003 and Exchange 2007

Recently, we have been seeing a number of issues where public folders cannot be replicated to Exchange 2007. The symptoms are:

1.       Exchange 2007 Mailboxes are not able to view Exchange 2003 Public Folders through Outlook client.

2.       On Exchange 2003 Server, the public folder replication messages are queued in the Messages with an unreachable destination queue.

3.       On Exchange 2003 Server, you may find event below:

Event Type:    Warning

Event Source:         MSExchangeTransport

Event Category:     Routing Engine/Service

Event ID:          951


When sending mail to the following address, we have found the connector with target domain *.5B2DCAE3-0882-1148-8DEB-B36F641F9E2B matching destination address exists in DS. However, we have no way of getting there. You need to check your topology and add appropriate connectors among Routing Groups.


The root cause is that there is no Routing Group Connector between Exchange 2003 RG and Exchange 2007 RG. During Exchange 2007 installation, there is an option to select an Exchange 2000/2003 Routing Group Connector Bridge Head Server. If you do not configure this option, the Routing Group Connector won’t be created between the default routing group in Microsoft Exchange Server 2007 and Exchange Server 2003 routing groups.


Note: The first routing group connector between Exchange 2007 and Exchange 2003 or Exchange 2000 is created and configured during installation of the first Hub Transport Server role in an existing Exchange organization.


To resolve this issue, you can use the Exchange Management Shell to manually create the routing group connector.

For example, run the following command to create reciprocal routing group connectors between the Exchange 2007 routing group and the routing group that is associated with the specified Exchange Server 2003 server, assign a cost of 100 to that connector, and enable public folder referrals:


New-RoutingGroupConnector -Name "Interop RGC" -SourceTransportServers "" -TargetTransportServers "" -Cost 100 -Bidirectional $true -PublicFolderReferralsEnabled $true


Comments (15)

  1. Rhiu says:

    Hi all,

    I’ve alreay found a solution for this problem. The smart host configured in Exchange 2000 was the caused of the problem. After removing it and setting up an SMTp connector instead, email sending worked fine. After that, I recreate a public folder database on exchange 2007 and restart the replication.

  2. Rhiu says:

    Guys, anyone who can help me with this problem. I’ve been trying a lot of possible solutions but still ends up with no replication at all.

    I’m receiving a lot of errors and replication warnings.

    Also, I can email from Exchange 2007 to Exchange 2003 but not vice versa. I’m almost ground zero on this issue.


  3. Walter J. Hogan says:

    Thanks for the information. I found this post after a long search. Errors during installation were ignored per a post on another site and I believe that led to the connector not ever getting created. You saved me a huge headache.

  4. LakshmiNarayana says:

    Thanks a lot for the post.

    I was struck with Schedule free busy sync across 2k & 2k7 Org. Update was coming till exchange 2k3. but was not repliacating to 2k7.

    issue resolved with connector, as detailed in the article.

    thanks again

    Lakshmi Narayana

  5. freddie says:

    We did select and existing Exchange 2000 Server during the installation process, but still get the error? The Outlook client on the Exchange 2007 server gets "The set of folders could not be open" message each time they click on the Public Folders area. Any suggestions

    Any help will be surely appreciated…


  6. paul says:

    Hello, i have the same issue… i created the RGC via Exchange Management Shell but i still have the messages qued, i can send messages from 2007 to 2003 but not from 2003 to 2007.


  7. Tom Breit says:

    You really need to spell ‘supportability’ with quote marks around it. Migrating (or, as we’re calling it now, transitioning’ from Exchange 2003 to 2007, particularly when the site has previously been upgraded from Exchange 5.5, is a freaking nightmare. It’s a tossup whether it’s better to tell the users the server crashed, and we need to install Exchange 2007 from scratch.

  8. Sohrab says:

    Hello, I have exactly the issue as described by Paul. I can send messges from 2007 to 2003 but not vice versa. Also the RGC was created during the installation and I can see all the mails in queue on Exchange 2003 Server. How can I get the RGC work from 2003 to 2007, can anyone help? Once RGC works, the PF replication should happen and the transition can be smooth.


  9. exchange2007-admin says:

    same problem as sohrab – any ideas?

  10. decc says:

    Same problem as Sohrab. Created the connector during installation. Created another conector using the above script but all PF messages still stuck in the queue ?

  11. Rhiu says:

    I have the same problem. would anyone can help me.

    Public folder emails get stuck on queue in exchange server 2007.. I can send email from 2000 to 2007 but not vice versa.

    I have configured the routing group connector but to no avail, the public folder replication just stopped.

    Please help.

  12. Rhiu says:


    I have another problem, anyone.. please help. I am about to decommission the old Microsoft Exchange 2000 Server after I have replicated the public folders. When we proceed in deleting the public folder in the Exch2k, all of a sudden, all replicated public folders cannot be viewed. You can see that the items are there but you cannot view it, anyone who knows the root cause of this problem. BTW, I have deleted first the Routing group Connectors before deleting the Public Folder store, is it possible it was the caused of the problem.

    Anyone here.. please help.


  13. Bret W says:

    Thank You very much for this anwser. As with many others here this bugged me for 3 days

  14. Mark says:

    Thank you very much, helped me greatly with a migration from 2003-2011, when I likely jumped the gun and deleted the connector.

  15. JohnnyBCNY says:

    Thanks for this, I used this for a SBS 2003 to Exchange 2010 migration that was stuck migrating the public folders. The same command worked in the 2010 EMS and immediately solved my issue with the messages being stuck in the queue.

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