Permitir que el usuario intente conectarse de nuevo después de que la autenticación falle acceso_denegado

Solución del problema

En su Startup.cs, separe el estado fallido en otro método como este:

 public void Configuration(IAppBuilder app)
 {
 app.SetDefaultSignInAsAuthenticationType(CookieAuthenticationDefaults.AuthenticationType);
 app.UseCookieAuthentication(new CookieAuthenticationOptions());
 app.UseOpenIdConnectAuthentication(
 new OpenIdConnectAuthenticationOptions
 {
 // Sets the ClientId, authority, RedirectUri as obtained from web.config
 ClientId = clientId,
 Authority = authority,
 RedirectUri = redirectUri,
 // PostLogoutRedirectUri is the page that users will be redirected to after sign-out. In this case, it is using the home page
 PostLogoutRedirectUri = redirectUri,
 Scope = OpenIdConnectScope.OpenIdProfile,
 // ResponseType is set to request the code id_token - which contains basic information about the signed-in user
 ResponseType = OpenIdConnectResponseType.CodeIdToken,
 // OpenIdConnectAuthenticationNotifications configures OWIN to send notification of failed authentications to OnAuthenticationFailed method
 Notifications = new OpenIdConnectAuthenticationNotifications
 {
  AuthenticationFailed = OnAuthenticationFailed
 }
 }
 );
 }
 /// <summary>
 /// Handle failed authentication requests by redirecting the user to the home page with an error in the query string
 /// </summary>
 /// <param name="context"></param>
 /// <returns></returns>
 private Task OnAuthenticationFailed(AuthenticationFailedNotification<OpenIdConnectMessage, OpenIdConnectAuthenticationOptions> context)
 {
 context.HandleResponse();
 context.Response.Redirect("/?errormessage=" + context.Exception.Message);
 return Task.FromResult(0);
 }