Dear all,

I have the issue with number of the users who can't connect to the mailbox after migration from 2010 to 2013 Exchange server. 

If I go to Exchange Proxy settings in Outlook it still points to old URL records, when I change URL to the Exchange 2013 it works ok, but after closing the Outlook the problem appears again.

Mailboxes are copied to Exchange 2013 without any problems

Please, help

Thank you in advance

Hello

wich version outlook client heve?

https://support.microsoft.com/en-us/kb/2934750

sometimes help recycle
MSExchangeAutodiscoverAppPool and MSExchangeSyncAppPool on all client acces server

Hi San,

Thank you for your question.

Did those uses come from the same database?

We could rebuild the profile to check if the issue persist.

Any user with a pre-existing Outlook profile configured to point to a CAS name and not the CAS array object will continue to connect to the CAS name and it will not update itself to utilize the CAS array object FQDN. 

The profile will not update itself because the client will not receive an ecWrongServer response from CAS. It will not receive this response because any CAS is a valid connection point for any mailbox database via RPC (over TCP) so clients can survive datacenter switchover/failover events without being reconfigured and all an admin has to do is flip the CAS array object DNS record to point to a surviving pool of CAS. Currently the only way to fix mailbox profiles would be a manual profile repair within Outlook, by publishing an Office PRF file via GPO (not going to work for non-domain joined machines), or by decommissioning the CAS server named in the users profiles so the endpoint is no longer available. This last option should (test test test!!) trigger a full profile repair by Autodiscover in Outlook 2007 or Outlook 2010. Outlook 2003 is only repairable with a profile repair or a PRF file. Autodiscover will not as of this articles writing update a profile to a new server name as part of the normal Autodiscover process which updates the Outlook Anywhere configuration and discovers EWS URLs for other features such as OOF Management, Free/Busy, and Inbox Rules management.

We could refer to the following link:

http://blogs.technet.com/b/exchange/archive/2012/03/28/demystifying-the-cas-array-object-part-2.aspx

If there are any questions regarding this issue, please be free to let me know.

Best Regard,

Jim

Thank you so much for you help. That problem was with some missing updates in MS office 2010. After installation of SP2 for the Office, the issue seems to be resolved now. 

Cheers