Thursday, 29 October 2015

Exchange 2010 - 2013 Migration: Outlook Client Issue

During an Exchange 2010 to 2013 migration, you may get into a situation where Outlook clients with mailboxes on Exchange 2010 can no longer connect to their mailboxes once the A record for Outlook Anywhere e.g. is changed to resolve to Exchange 2013.


Although there are a number of causes, this may be because the RpcClientAccessServer parameter on the Exchange 2010 mailbox databases is set to the same FQDN as the Outlook Anywhere hostname. This means that once you change the A record to resolve to Exchange 2013, the RPC/TCP clients will attempt to connect to the Exchange 2013 servers using RPC/TCP which won't work as this is no longer supported by Exchange 2013.

Usually Outlook Anywhere is enabled on Exchange 2010 but this is not always the case. If enabled, the clients *should* fail over to using Outlook Anywhere if they cannot connect using RPC/TCP on fast networks. If not enabled then clients will attempt to connect to Exchange 2013 using RPC/TCP and will fail. (Note that enabling Outlook Anywhere on Exchange 2010 is a required step in an Exchange 2010 to 2013 migration)


To resolve this issue, enable Outlook Anywhere on Exchange 2010 and force the Outlook clients to use HTTPS (Outlook Anywhere) on all connections. By default, on fast connections, Outlook will try to use RPC/TCP then HTTP and on slow connections Outlook will try to use HTTP first then RPC/TCP. This can be configured using Autodiscover by running the below commands from the Exchange Management Shell on Exchange 2010:

Set-OutlookProvider EXCH -OutlookProviderFlags:ServerExclusiveConnect

Set-OutlookProvider EXPR -OutlookProviderFlags:ServerExclusiveConnect

Once this is done, all Outlook clients on Exchange 2010 will be using Outlook Anywhere whether they are inside the office or not and you can change the A record to resolve to Exchange 2013 so Exchange 2013 can proxy the request for the Exchange 2010 users.

Any clients that don't support Outlook Anywhere need to be configured to use Exchange 2010 by adding specifying to resolve to the internal IP of your Exchange 2010 servers.

More information:
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1 comment:

  1. During Exchange migration from 2010 to 2013 you should consider these points:
    1. Acquainted with Release Notes
    2. Requirement of System
    3. Ensures Prerequisite steps are done
    4. Configure the Domain Name System (DNS)
    5. Choose OAB (Offline Address Book)
    6. Check legacy Domain Name System (DNS)
    7. Install Exchange 2013
    8. Prepare Exchange 2013 mailbox
    9. Virtual Directories (Exchange) configuration
    10. Configure of Digital Certification of Exchange 2010/2013
    11. Configure Send Connectors
    12. Deploy UM (Unified Messaging)
    13. Configuration of Outlook
    14. Ensure Virtual Directory Settings
    15. Testing of Exchange 2007 external URL’s
    16. DNS Record changing
    17. Migration of mailbox from Exchange 2010 to 2013
    18. Migration of public folder from Exchange 2013 to 2013
    19. Configuration of new Exchange 2013

    After applying all these steps while migration from Exchange 2013 to 2010, you fill not face any difficulty. If you face any difficulty then you go to another method Stellar Converter for EDB. This is most easily method to easily migration from Exchange 2013 to 2010. Through this method, you can ensure smooth, fast and secure migration.