title: Cannot send headers; headers already sent
body: <p>I`ve got a problem with the magento cart.</p>
  
  <p>Cannot send header; headers already sent /homepages/14/d412931110/htdocs/shop/app/code/local/BTS/Checkout/Model/Observer.php, line 91</p>
  
  <p>Report:</p>
  
  <pre><code>a:5:{i:0;s:137:"Cannot send headers; headers already sent in /homepages/14/d412931110/htdocs/shop/app/code/local/BTS/Checkout/Model/Observer.php, line 91";i:1;s:1601:"#0 /homepages/14/d412931110/htdocs/shop/lib/Zend/Controller/Response/Abstract.php(148): Zend_Controller_Response_Abstract-&gt;canSendHeaders(true)
  #1 /homepages/14/d412931110/htdocs/shop/app/code/core/Mage/Core/Controller/Response/Http.php(105): Zend_Controller_Response_Abstract-&gt;setRedirect('http://www.puet...', 302)
  #2 /homepages/14/d412931110/htdocs/shop/app/code/core/Mage/Core/Controller/Varien/Action.php(672): Mage_Core_Controller_Response_Http-&gt;setRedirect('http://www.puet...')
  #3 /homepages/14/d412931110/htdocs/shop/app/code/core/Mage/Checkout/controllers/CartController.php(92): Mage_Core_Controller_Varien_Action-&gt;_redirect('checkout/cart')
  #4 /homepages/14/d412931110/htdocs/shop/app/code/core/Mage/Checkout/controllers/CartController.php(225): Mage_Checkout_CartController-&gt;_goBack()
  #5 /homepages/14/d412931110/htdocs/shop/app/code/core/Mage/Core/Controller/Varien/Action.php(420): Mage_Checkout_CartController-&gt;addAction()
  #6 /homepages/14/d412931110/htdocs/shop/app/code/core/Mage/Core/Controller/Varien/Router/Standard.php(250): Mage_Core_Controller_Varien_Action-&gt;dispatch('add')
  #7 /homepages/14/d412931110/htdocs/shop/app/code/core/Mage/Core/Controller/Varien/Front.php(176): Mage_Core_Controller_Varien_Router_Standard-&gt;match(Object(Mage_Core_Controller_Request_Http))
  #8 /homepages/14/d412931110/htdocs/shop/app/code/core/Mage/Core/Model/App.php(349): Mage_Core_Controller_Varien_Front-&gt;dispatch()
  #9 /homepages/14/d412931110/htdocs/shop/app/Mage.php(640): Mage_Core_Model_App-&gt;run(Array)
  #10 /homepages/14/d412931110/htdocs/shop/index.php(80): Mage::run('', 'store')
  #11 {main}";s:3:"url";s:83:"/index.php/checkout/cart/add/uenc/aHR0cDovL3d3dy5wdWV0emNoZW4uY29tLw,,/product/229/";s:11:"script_name";s:10:"/index.php";s:4:"skin";s:7:"default";}
  </code></pre>
  
  <p>Do you have any solution for me please?</p>