title: Magento - Error after disabling modules
body: <p>I've disabled the Rss and Newsletter modules of my Magento 1.7 instance following the instructions of this post:</p>
  
  <p><a href="http://inchoo.net/ecommerce/magento/how-to-fully-disable-turn-off-magento-module/comment-page-1/#comment-65853" rel="nofollow">http://inchoo.net/ecommerce/magento/how-to-fully-disable-turn-off-magento-module/comment-page-1/#comment-65853</a></p>
  
  <p>I just edited the <code>app\etc\modules\Mage_All.xml</code> file by changing to <code>&lt;active&gt;false&lt;/active&gt;</code> in both <code>Mage_Rss</code> and <code>Mage_Newsletter</code> modules. </p>
  
  <p>The problem is that when I try to load a customer page through admin panel, I get the following error:</p>
  
  <blockquote>
    <p>Fatal error: Call to a member function loadByCustomer() on a
    non-object in app\code\core\Mage\Newsletter\Model\Subscriber.php on
    line 267</p>
  </blockquote>
  
  <p>Why is it happening? Why is this code being executing even though I've disabled such module?</p>
  
  <p>Thanks!</p>