NullReferenceException with Owin

Question

I just cloned the project to a new machine, and I get a hard debugging NullReferenceException on the MVC site using OWIN:

 [NullReferenceException: Object reference not set to an instance of an object.] Microsoft.Owin.Security.Cookies.<AuthenticateCoreAsync>d__0.MoveNext() +664 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.<BaseInitializeAsync>d__2.MoveNext() +860 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.<Invoke>d__0.MoveNext() +427 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 

It happens after

 [assembly: OwinStartupAttribute(typeof(Website.Startup))] namespace Website { public partial class Startup { public void Configuration(IAppBuilder app) { ConfigureAuth(app); } } } 

but as far as I can tell F10ing after that, throws an exception - it never reaches the constructor of the first controller.

Has anyone experienced this before and / or can point me in the direction of what could be causing the error?

Answer 1

Updating OWIN from v2 to v3 seems to fix this problem.

It is worth noting that all packages related to OWIN must also be updated.

Answer 2

The solution above did not help me, however I finally found the answer after many attempts.

I am developing several solutions at the same time, and something must be confused in the localhost cookies (each solution runs on a different localhost port). After clearing my localhost cookies, the problem was resolved.

Answer 3

An upgrade from OWIN v3.0 to v3.1 fixed the problem for me.