FIX: Outlook clients that use MAPI over HTTP to connect to Microsoft Exchange Server 2013 mailboxes are intermittently disconnected

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Symptoms

Microsoft Outlook clients that use MAPI over HTTP to connect to Microsoft Exchange Server 2013 mailboxes are intermittently disconnected. For example, Cached Mode users see a Disconnected message displayed on the Outlook status bar. Also, Online Mode users receive the following error message when they try to start Outlook:

Cannot start Microsoft Outlook. Cannot open the Outlook window. The set of folders cannot be opened. You must connect to Microsoft Exchange with the current profile before you can synchronize your folders with your Outlook data file (.ost).

Additionally, the following events are logged in the Application log in Event Viewer on the affected server that's running Exchange Server 2013:

Log name: Application
ID: 1309
Level: Warning
Source: ASP.NET 4.0.30319.0
Message: Event code: 3005
Event message: An unhandled exception has occurred.
Event ID: 35ca26135b3f454b900e631af67eeec8
Event sequence: 2
vent occurrence: 1
Event detail code: 0
 
Application information:
Application Virtual Path: /mapi/nspi
Application Path: D:\Exchange\V15\ClientAccess\mapi\nspi\
 
Process information:
Process ID: 5096
Process name: w3wp.exe
Account name: NT AUTHORITY\SYSTEM
 
Exception information:
Exception type: HttpException
Exception message: RpcObjectSetType
  at System.Web.HttpApplicationFactory.EnsureAppStartCalledForIntegratedMode(HttpContext context, HttpApplication app)
  at System.Web.HttpApplication.RegisterEventSubscriptionsWithIIS(IntPtr appContext, HttpContext context, MethodInfo[] handlers)
  at System.Web.HttpApplication.InitSpecial(HttpApplicationState state, MethodInfo[] handlers, IntPtr appContext, HttpContext context)
  at System.Web.HttpApplicationFactory.GetSpecialApplicationInstance(IntPtr appContext, HttpContext context)
  at System.Web.Hosting.PipelineRuntime.InitializeApplication(IntPtr appContext)
 
RpcObjectSetType
  at Microsoft.Exchange.Rpc.RpcServerBase.ThrowRpcException(String message, Int32 rpcStatus)
  at Microsoft.Exchange.Rpc.ProcessAccess.ProcessAccessRpcServer.RegisterInterface(Void* ifSpec, ValueType mgrTypeGuid, _GUID* pMgrTypeUuid, Void* pMgrEpv, UInt32 flags, UInt32 maxCalls)
  at Microsoft.Exchange.Rpc.RpcServerBase.RegisterServer(Type type, ObjectSecurity sd, UInt32 desiredAccess, ValueType mgrTypeGuid, Void* mgrEpv, String annotation, Boolean isLocalOnly, Boolean autoListen, UInt32 maxCalls)
  at Microsoft.Exchange.Data.ApplicationLogic.ProcessAccessManager.RegisterComponent(IDiagnosable diagnosable)Request information:
Request path: /mapi/nspi/
User: 
Is authenticated: False
Authentication Type: 
Thread account name: NT AUTHORITY\SYSTEM
 
Thread information:
Thread ID: 64
Thread account name: NT AUTHORITY\SYSTEM
Is impersonating: False
Stack trace: at System.Web.HttpApplicationFactory.EnsureAppStartCalledForIntegratedMode(HttpContext context, HttpApplication app)
  at System.Web.HttpApplication.RegisterEventSubscriptionsWithIIS(IntPtr appContext, HttpContext context, MethodInfo[] handlers)
  at System.Web.HttpApplication.InitSpecial(HttpApplicationState state, MethodInfo[] handlers, IntPtr appContext, HttpContext context)
  at System.Web.HttpApplicationFactory.GetSpecialApplicationInstance(IntPtr appContext, HttpContext context)
  at System.Web.Hosting.PipelineRuntime.InitializeApplication(IntPtr appContext)