After you install and upgrade to Microsoft Exchange Server 2016 Cumulative Update 6 (CU6), you can't access Outlook Web App (OWA) or Exchange Control Panel (ECP), and you receive the following error message:
We can't get that information right now. Please try again later.
X-ClientId: ClientID
X-FEServer: Exch1
In addition, the following events information is recorded in the Application log of the Exchange server that hosts the mailbox database:
Source: MSExchange OAuth
Event ID: 2004
Task Category: Configuration
Level: Warning
Keywords: Classic
User: N/A
Computer: mail.contoso.com
Description:
Unable to find the certificate with thumbprint CertificateValue in the current computer or the certificate is missing private key. The certificate is needed to sign the outgoing token.
Source: ASP.NET 4.0.30319.0
Event ID: 1309
Task Category: Web Event
Level: Warning
Keywords: Classic
User: N/A
Description:
Event code: 3005
Event message: An unhandled exception has occurred.
Event ID: EventID
Event sequence: 2
Event occurrence: 1
Event detail code: 0
Application information:
Application domain: /LM/W3SVC/2/ROOT/owa-2-DomainID
Trust level: Full
Application Virtual Path: /owa
Application Path: C:\Program Files\Microsoft\Exchange Server\V15\ClientAccess\owa\
Machine name: Exch1
Process information:
Process ID: 21508
Process name: w3wp.exe
Account name: NT AUTHORITY\SYSTEM
Exception information:
Exception type: TargetInvocationException
Exception message: Exception has been thrown by the target of an invocation.
at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)
at System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments)
at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
at Owin.Loader.DefaultLoader.<>c__DisplayClass12.<MakeDelegate>b__b(IAppBuilder builder)
at Owin.Loader.DefaultLoader.<>c__DisplayClass1.<LoadImplementation>b__0(IAppBuilder builder)
at Microsoft.Owin.Host.SystemWeb.OwinAppContext.Initialize(Action`1 startup)
at Microsoft.Owin.Host.SystemWeb.OwinBuilder.Build(Action`1 startup)
at Microsoft.Owin.Host.SystemWeb.OwinHttpModule.InitializeBlueprint()
at System.Threading.LazyInitializer.EnsureInitializedCore[T](T& target, Boolean& initialized, Object& syncLock, Func`1 valueFactory)
at Microsoft.Owin.Host.SystemWeb.OwinHttpModule.Init(HttpApplication context)
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)
at Microsoft.Exchange.Security.Authentication.Utility.GetCertificates()
at Microsoft.Exchange.Clients.Owa2.Server.Core.notifications.SignalR.SignalRStartup.Configuration(IAppBuilder app)
Request information:
Request URL: https://mail.contoso.com:URLID/owa/?bO=1
Request path: /owa/
User host address: UserHostAddressC:\Program Files\Microsoft\Exchange Server\V15\ClientAccess\owa\
User:
Is authenticated: False
Authentication Type:
Thread account name: NT AUTHORITY\SYSTEM
Thread information:
Thread ID: 24
Thread account name: NT AUTHORITY\SYSTEM
Is impersonating: False
Stack trace: at System.RuntimeMethodHandle.InvokeMethod(Object target, Object[] arguments, Signature sig, Boolean constructor)
at System.Reflection.RuntimeMethodInfo.UnsafeInvokeInternal(Object obj, Object[] parameters, Object[] arguments)
at System.Reflection.RuntimeMethodInfo.Invoke(Object obj, BindingFlags invokeAttr, Binder binder, Object[] parameters, CultureInfo culture)
at Owin.Loader.DefaultLoader.<>c__DisplayClass12.<MakeDelegate>b__b(IAppBuilder builder)
at Owin.Loader.DefaultLoader.<>c__DisplayClass1.<LoadImplementation>b__0(IAppBuilder builder)
at Microsoft.Owin.Host.SystemWeb.OwinAppContext.Initialize(Action`1 startup)
at Microsoft.Owin.Host.SystemWeb.OwinBuilder.Build(Action`1 startup)
at Microsoft.Owin.Host.SystemWeb.OwinHttpModule.InitializeBlueprint()
at System.Threading.LazyInitializer.EnsureInitializedCore[T](T& target, Boolean& initialized, Object& syncLock, Func`1 valueFactory)
at Microsoft.Owin.Host.SystemWeb.OwinHttpModule.Init(HttpApplication context)
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)