title: Drupal 7 Clean URLs won't enable
body: <p>On my installation the checkbox is visible to enable clean URLs.</p>
  
  <p>When you check it and click Save, it reloads the page with the checkbox no longer checked. Why is this?</p>
  
  <p>FYI you can access the page using the clean URL version: /admin/config/search/clean-urls</p>