Cannot save ConfigurationSection in Startup.cs - web API

Question

I cannot save my custom ConfigurationSectionin my web.configfile at startup.

I have completed this tutorial for general implementation. My unit tests have passed, I can save de ConfigurationSectionin my unit tests!

When starting the application, I want to build ClaimCollectionbased on the name of the controller class and the names of the membership method:

Startup.cs

public void Configuration(IAppBuilder app)
{

    Config = new HttpConfiguration();

    BuildUnityContainer();

    BuildClaimCollection(); <----------------

    ConfigureOAuth(app);

    WebApiConfig.Register(Config);
    app.UseCors(Microsoft.Owin.Cors.CorsOptions.AllowAll);
    app.UseWebApi(Config);

}

public void BuildClaimCollection()
{

    //config section
    MethodClaimSection methodClaimSection = BaseConfigurationSection<MethodClaimSection>.Open();

    var methods = GetClaimAuthorizedMethods();

    foreach (var method in methods)
    {
        var claimValue = GetClaimValueFromMethodName(method);
        var claim = new MethodClaimElement()
        {
            Type = "Method",
            Value = claimValue
        };

        methodClaimSection.MethodClaims.Add(claim);
    }
    methodClaimSection.Save();
}  

BaseConfigurationSection.cs

public abstract class BaseConfigurationSection<T> : ConfigurationSection
             where T : ConfigurationSection, new()
{
    public void Save()
    {
        System.Configuration.Configuration config = BaseConfigurationSection<T>.GetConfiguration();
        T section = (T)config.Sections[typeof(T).Name];

        foreach (var property in this.GetType().GetProperties())
        {
            if (property.IsDefined(typeof(ConfigurationPropertyAttribute), false))
            {
                section.GetType().InvokeMember(property.Name, BindingFlags.SetProperty, null, section, 
                    new object[] { 
                        .GetType().InvokeMember(property.Name, BindingFlags.GetProperty, null, this, null) 
                        });
            }
        }

        config.Save(ConfigurationSaveMode.Full);
    }
}

When I launch the WebApi application, I get this error:

Unable to access the remote object. Object Name: "System.Web.Http.HttpServer".

Stacktrace:

[ObjectDisposedException: .      : "System.Web.Http.HttpServer".]        System.Net.Http.DelegatingHandler.CheckDisposed() +332772        System.Net.Http.DelegatingHandler.CheckDisposedOrStarted() +13        System.Net.Http.DelegatingHandler.set_InnerHandler ( HttpMessageHandler) +23        System.Web.Http.HttpServer.Initialize() +108        System.Web.Http.HttpServer.b__b() +31        System.Threading.LazyInitializer.EnsureInitializedCore(T & target, Boolean & initialized, Object & syncLock, Func`1 valueFactory) +115        System.Threading.LazyInitializer.EnsureInitialized(T & target, Boolean & initialized, Object & syncLock, Func`1 valueFactory) +72        System.Web.Http.HttpServer.EnsureInitialized() +119        System.Web.Http.d__0.MoveNext() +276        System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess( ) +3897072        System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification( ) +58        System.Runtime.CompilerServices.TaskAwaiter`1.GetResult() +28        System.Web.Http.Owin.d__0.MoveNext() +1139        System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess( ) +3897072        System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification( ) +58        System.Runtime.CompilerServices.TaskAwaiter.GetResult() +26        Microsoft.Owin.Cors.d__0.MoveNext() +1204        System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess( ) +3897072        System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification( ) +58        System.Runtime.CompilerServices.TaskAwaiter.GetResult() +26        Microsoft.Owin.Host.SystemWeb.IntegratedPipeline.d__5.MoveNext() +287        System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess( ) +3897072        System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification( ) +58        System.Runtime.CompilerServices.TaskAwaiter.GetResult() +26        Microsoft.Owin.Security.Infrastructure.d__0.MoveNext() +937        System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess( ) +3897072        System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification( ) +58        System.Runtime.CompilerServices.TaskAwaiter.GetResult() +26        Microsoft.Owin.Security.Infrastructure.d__0.MoveNext() +937        System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess( ) +3897072        System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification( ) +58        System.Runtime.CompilerServices.TaskAwaiter.GetResult() +26        Microsoft.Owin.Host.SystemWeb.IntegratedPipeline.d__5.MoveNext() +287        System.Runtime.CompilerServices.TaskAwaiter.ThrowForNonSuccess( ) +3897072        System.Runtime.CompilerServices.TaskAwaiter.HandleNonSuccessAndDebuggerNotification( ) +58        System.Runtime.CompilerServices.TaskAwaiter.GetResult() +26        Microsoft.Owin.Host.SystemWeb.IntegratedPipeline.d__2.MoveNext() +272        System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw() +26        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, Boolean ) +155

Dispose...

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