Why is [Owin] throwing a null exception on new project?

Question

I have a rather strange issue i'm not sure how to fix or if i can even fix it.

I've done some research into the issue but can't find an answer to what's causing it.

I'm following a rather simple guide at http://www.asp.net/mvc/tutorials/mvc-5/create-an-aspnet-mvc-5-app-with-facebook-and-google-oauth2-and-openid-sign-on

and after enabling SSL and changing the controller to require https i get the following error:

Server Error in '/' Application.

Object reference not set to an instance of an object.

Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.NullReferenceException: Object reference not set to an instance of an object.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:

[NullReferenceException: Object reference not set to an instance of an object.]
Microsoft.Owin.Security.Cookies.CookieAuthenticationProvider.Exception(CookieExceptionContext context) +49
Microsoft.Owin.Security.Cookies.d__2.MoveNext() +3698 System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +93
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +52 System.Runtime.CompilerServices.TaskAwaiter`1.GetResult() +24 Microsoft.Owin.Security.Infrastructure.d__0.MoveNext() +810 System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +93
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +52 System.Runtime.CompilerServices.TaskAwaiter.GetResult() +21 Microsoft.Owin.Security.Infrastructure.d__0.MoveNext() +427 System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +93
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +52 System.Runtime.CompilerServices.TaskAwaiter.GetResult() +21 Microsoft.AspNet.Identity.Owin.d__0.MoveNext() +641 System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +93
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +52 System.Runtime.CompilerServices.TaskAwaiter.GetResult() +21 Microsoft.AspNet.Identity.Owin.d__0.MoveNext() +641 System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +93
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +52 System.Runtime.CompilerServices.TaskAwaiter.GetResult() +21 Microsoft.AspNet.Identity.Owin.d__0.MoveNext() +641 System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +93
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +52 System.Runtime.CompilerServices.TaskAwaiter.GetResult() +21 Microsoft.Owin.Host.SystemWeb.IntegratedPipeline.d__5.MoveNext() +287 System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess(Task task) +93
System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification(Task task) +52 System.Runtime.CompilerServices.TaskAwaiter.GetResult() +21 Microsoft.Owin.Host.SystemWeb.IntegratedPipeline.d__2.MoveNext() +272 System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() +22 Microsoft.Owin.Host.SystemWeb.Infrastructure.ErrorState.Rethrow() +33 Microsoft.Owin.Host.SystemWeb.IntegratedPipeline.StageAsyncResult.End(IAsyncResult ar) +150
Microsoft.Owin.Host.SystemWeb.IntegratedPipeline.IntegratedPipelineContext.EndFinalWork(IAsyncResult ar) +42
System.Web.AsyncEventExecutionStep.System.Web.HttpApplication.IExecutionStep.Execute() +415 System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +155

Version Information: Microsoft .NET Framework Version:4.0.30319; ASP.NET Version:4.0.30319.34237

Turning off SSL fixes the issue, I also know that commenting out the startup.auth in app_start fixes the issue on SSL.

Does anyone know why this is happening?

Answer 1

Similar to Sandeep's answer, I also updated the cookie authentication provider. Except, instead of swallowing the error I threw the exception so you could see what the underlying problem was:

app.UseCookieAuthentication(new CookieAuthenticationOptions
{
    AuthenticationType = DefaultAuthenticationTypes.ApplicationCookie,
    LoginPath = new PathString("/Account/Login"),
    Provider = new CookieAuthenticationProvider
    {
        // Enables the application to validate the security stamp when the user logs in.
        // This is a security feature which is used when you change a password or add an external login to your account.  
        OnValidateIdentity = SecurityStampValidator.OnValidateIdentity<ApplicationUserManager, User>(
            validateInterval: TimeSpan.FromMinutes(30),
            regenerateIdentity: (manager, user) => user.GenerateUserIdentityAsync(manager)),

            /* I changed this part */
            OnException = (context =>
            {
                throw context.Exception;
            })
    }                
});

The underlying problem for me was that I had changed the model and forgotten to add a new migration.