No Free/Busy info after mailbox moves from Exchange 2010 to Exchange 2013 or Exchange 2016

Applies to: Exchange Server 2016 Enterprise EditionExchange Server 2016 Standard EditionExchange Server 2013 Enterprise More

Symptoms


When Outlook mailboxes are moved to Microsoft Exchange Server 2013 or Exchange Server 2016, users can no longer see free/busy information.

This issue occurs in the following scenario:
  • The user's mailbox is moved to Exchange Server 2013 or Exchange Server 2016.
  • After the mailbox is moved and the user tries to look up free/busy information for another user in the organization, they see hash marks instead of the expected time blocks.
  • Outlook eventually succeeds in looking up free/busy info if the user waits for 12 hours or longer.

Cause


After the mailbox move is complete, Exchange Server 2013 or Exchange Server 2016 continues to proxy the EWS request to Exchange Server 2010. Exchange Server 2010 responds with a 302 redirect back to Exchange Server 2013 or Exchange Server 2016 (depending on the upgrade).

Resolution


To resolve this issue, run the following commands to restart the Autodiscover Application Pool and the Exchange Web Services Application Pool on the Exchange Server 2013 or Exchange Server 2016 servers:

Restart-WebAppPool MSExchangeAutodiscoverAppPool

Restart-WebAppPool MSExchangeServicesAppPool

More Information


When this issue occurs, the HTTPProxy\EWS logs contain information that resembles the following:

2016-09-20T13:07:56.303Z,a39c60bc-59ed-4eb3-b819-a1a5d3093f25,15,1,466,33,{0EBC3FE9-9769-4C23-872B-03327B4F3B98},Ews,mail.fabrikam.com,/EWS/exchange.asmx,,Negotiate,true,FABRIKAM\user8,,Sid~S-1-5-21-1836938974-4219133062-1266341204-7604,Microsoft Office/15.0 (Windows NT 6.1; Microsoft Outlook 15.0.4859; Pro),192.168.17.103,E16SRV01,500,500,,POST,Proxy,E14SRV01.fabrikam.com,14.03.0123.000,IntraForest,WindowsIdentity,,,,679,629,,,3,0,,0,,0,,0,0,,0,10,0,0,0,0,4,0,0,1,0,0,7,0,5,2,2,5,10,,,,BeginRequest=2016-09-20T13:07:56.288Z;CorrelationID=<empty>;ProxyState-Run=None;DownLevelTargetRandomHashing=0/2;ClientAccessServer=E14SRV01.fabrikam.com;ResolveCasLatency=0;FEAuth=BEVersion-1937997947;ProxyToDownLevel=True;RoutingEntry=DatabaseGuid:c63d4857-c93b-463e-b469-41c1cf370c2e%40fabrikam.com%40fabrikam.com Server:E16SRV01.fabrikam.com+1937937997@0;BeginGetRequestStream=2016-09-20T13:07:56.288Z;OnRequestStreamReady=2016-09-20T13:07:56.288Z;MailboxServerByServerGuard_E14SVR1.fabrikam.com=1;MailboxServerByForestGuard_fabrikam.com=1;TotalMailboxServerGuard=1;BeginGetResponse=2016-09-20T13:07:56.288Z;OnResponseReady=2016-09-20T13:07:56.303Z;EndGetResponse=2016-09-20T13:07:56.303Z;ProxyState-Complete=ProxyResponseData;SharedCacheGuard=0;EndRequest=2016-09-20T13:07:56.303Z;S:ServiceCommonMetadata.Cookie=25d94679e2034a1e9f61c3b217f6563b,WebExceptionStatus=ProtocolError;ResponseStatusCode=500;