为什么我的Azure网站不接受OAuth令牌？

我希望我的应用程序在使用Azure网站托管时接受OAuth令牌。我有以下内容：

Web应用程序的web.config

<appSettings>
  <add key="ida:Realm" value="https://example.com/development" />
  <add key="ida:AudienceUri" value="https://example.com/development" />
  <add key="ida:Tenant" value="example.com" />
</appSettings>

Web应用程序的Startup.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;
using Microsoft.AspNet.SignalR;
using Microsoft.Owin;
using Owin;
using Microsoft.Owin.Security.ActiveDirectory;
using System.Configuration;
[assembly: OwinStartup(typeof(MyApplication.Web.Startup))]

namespace MyApplication.Web
{
    public class Startup
    {
        public void Configuration(IAppBuilder app)
        {    
            ConfigureAuth(app);
        }

        public void ConfigureAuth(IAppBuilder app)
        {
            app.UseWindowsAzureActiveDirectoryBearerAuthentication(
                new WindowsAzureActiveDirectoryBearerAuthenticationOptions
                {
                    TokenValidationParameters = new System.IdentityModel.Tokens.TokenValidationParameters()
                    {
                        ValidAudience = ConfigurationManager.AppSettings["ida:AudienceUri"]
                    },
                    Tenant = ConfigurationManager.AppSettings["ida:Tenant"]
                });
        }
    }
}

Main.cs

using Microsoft.IdentityModel.Clients.ActiveDirectory;
using System.Globalization;
using System.Net.Http;
using System.Net.Http.Headers;

void Main()
{
    var clientId = @"GUIDGUIDGUID";
    var key = @"KEYKEYKEYKEYKEY";
    var aadInstance = "https://login.windows.net/{0}";
    var tenant = "example.com";
    var authContext = new AuthenticationContext(String.Format(CultureInfo.InvariantCulture, aadInstance, tenant), true);
    var credential = new ClientCredential(clientId, key);
    authContext.TokenCache.Clear();
    var token = authContext.AcquireToken(@"https://example.com/development", credential);
    using (var client = new HttpClient())
    {
        client.DefaultRequestHeaders.Authorization = new AuthenticationHeaderValue("Bearer", token.AccessToken);
        var response = client.GetAsync(@"https://app.example.com/").Result;
        var responseText = response.Content.ReadAsStreamAsync().Result;
        Console.Write(new StreamReader(responseText).ReadToEnd());
    }
}

谁能提供一些指导？