Outlook 2007 connection issues to Exchange 2013 RRS feed

  • Question

  • Hi im experiencing a rather strange problem with some Outlook 2007 clients.

    I have a Exchange 2007 infrastructure in coexistance with Exchange 2013:

    • All DNS records correctly setted up
    • All URLs and autodiscovery correctly setted up
    • 75 clients with Outlook 2007 and 2013 were migrated to Exch 2013 and are working correctly

    All seems right from the infrastructure side, but I m having 6 mbxs (migrated to Exch 2013) that cannot connect.

    Running outlook /rpcdiags shows:

    • Directory - Connected to FQDN of DC [Here I should have mbxguid] 
    • Mail - Connecting... to [mbxguid]@[domain] - This connection retries several times

    The mail connection retries several times till it fails with: Cannot start microsoft outlook. Cannot open outlook window....

    So.. I already check the usual suspects:

    • Outlook 2007 has the Nov 2012 patch
    • Client can resolve all URLs
    • Encypt connection is enabled
    • Correct Outlook Anywhere settings

    After that I repaired the profile and outlook connected, to my surprise when I checked rpcdiag I got:

    • Directory - Connected to FQDN of DC 
    • Mail - Connected to FQDN of Exch 2013 MBX Server 

    Never saw a client connecting with FQDN to an Exch 2013....

    The next day the error shows up again and the temporal solution is to repair the profile, and having the same results.

    I check if the "DS Server" value in HKEY_CURRENT_USER\Software\Microsoft\Exchange\Exchange Provider was configured on the client and server side, but it was not present:


    Why would those particular Outlooks try to connect with the FQDN instead of the MBX Guid?


    Monday, May 14, 2018 7:40 PM


  • The port 443 was blocked in some VLANs, so the client was behaving stangely after getting the autodiscover response.
    • Marked as answer by JoaquinGomez Wednesday, May 30, 2018 3:56 PM
    Wednesday, May 30, 2018 3:56 PM