I am trying to call App:abort(404) during a boot hook in my custom service provider, but when i call it the following error occurs:

Undefined Symfony\Component\HttpKernel\Exception\NotFoundHttpException in /backend/vendor/laravel/framework/src/Illuminate/Foundation/Application.php line 901

Any guidance on how to resolve this would be appreciated.

If it helps, here is sudo code of what i want to achieve:

<?php

namespace MyPlugin;

use App;
use October\Rain\Support\ModuleServiceProvider;
use Request;
use Redirect;

class ServiceProvider extends ModuleServiceProvider
{
    public function boot()
    {
          // Check user can access site.
        if ($this->userHasAccess() === FALSE)
        {
            App::abort(403);
        }
        // Check if hidden from user.
       if ($this->hiddenFromUser() === TRUE)
       {
           App::abort(404);
       }
    }
}

Both calls to App::abort() trigger the error. It seems like Symfony\Component\HttpKernel\Exception\NotFoundHttpException is not being auto loaded correctly.