title: Paypal integration with Yii
body: <p>This is my Directory Structure in yii</p>
  
  <p>Project-Name</p>
  
  <pre><code>   Source Files
         Protected
           -&gt;controlleres
           -&gt;Vendors
  </code></pre>
  
  <p>In vendors I have paypal merchant sdk.</p>
  
  <p>In controller I have written an action which calls setExpressCheckout, but I am getting the following error :</p>
  
  <p>include(PayPalAPIInterfaceServiceService.php): failed to open stream: No such file or directory</p>
  
  <p>Please help me out.</p>
  
  <p>Thanks in Advance.</p>