Codeigniter没有找到文件url帮助器

Question

So I have this setup:

<a href="<?php echo base_url();?>artistas/index" class="menu-link effect link">ARTISTAS</a>

But when I click on that link, it takes me to http://localhost/Universal%20Music/Universal/artistas/index which says 404, like if there's nothing there but I've already created the controller with that name loading some views in it. Am I missing something here?

EDIT

My config.php has:

$config['base_url'] = 'http://localhost/Universal/Universal';

I stop using spaces in the names of the folders and now the path is: C:\Users\Horacio\Documents\Projects\Universal\Universal

The controller file has the same name of the class I need and the code inside is:

<?php
class Artistas extends CI_Controller {

   function __construct() {
       parent::__construct();
   }


    public function index()
    {
        $this->load->view('header');
        $this->load->view('main-index');
    }
}