title: CSRF validation failed in Drupal
body: <p>I'm using a webservice in Drupal 7. If I try to use <a href="https://addons.mozilla.org/en-US/firefox/addon/poster/" rel="nofollow">Poster</a> I get '<a href="https://en.wikipedia.org/wiki/Cross-site_request_forgery" rel="nofollow">CSRF</a> validation failed'. Before, I was connected with an administrator account.</p>
  
  <p>I use the Firefox add-in <a href="https://addons.mozilla.org/en-US/firefox/addon/poster/" rel="nofollow">Poster</a>.</p>
  
  <p>How can I fix this problem?</p>