title: TCPDF PDF forms, signing certificates and how to enable user's rights
body: <p>This is driving me completely and utterly nuts... Basically I have a PDF form generated by TCPDF and want to set the user rights (using setUserRights) for that PDF so that users can save the form with the data they inputted. The TCPDF manual isn't really helpful at this particular point and states that you need a "signing certificate" to enable saving and other extended features.</p>
  
  <p>So I generated an SSL certificate and private using OpenSSL and "imported" them using the  setSignature method. Without using that method Adobe Reader moans:</p>
  
  <blockquote>
    <p>This document enabled extended
    features in Adobe Reader. The document
    has been changed since it was created
    and use of extended features is no
    longer available. Please contact the
    author for the original version of
    this document.</p>
  </blockquote>
  
  <p>When the required setSignature method is set that message doesn't appear, but Reader still can't save the PDF.</p>
  
  <pre><code>$this-&gt;Pdf-&gt;setSignature("file:///certificates/forms.crt", "file:///certificates/forms.key", "somepassword", "", 3);
  </code></pre>
  
  <p>And then I set full user rights:</p>
  
  <pre><code>$this-&gt;Pdf-&gt;setUserRights(true, '/FullSave', '/Create/Delete/Modify/Copy/Import/Export', '/Add/Delete/FillIn/Import/Export/SubmitStandalone/SpawnTemplate', '/Modify');
  </code></pre>
  
  <p>Has anybody worked with this particular feature and is able to point out what I'm doing wrong here?</p>
  
  <p><strong>Update</strong></p>
  
  <p>TCPDF includes <a href="http://www.tecnick.com/pagefiles/tcpdf/example_052.phps" rel="nofollow noreferrer">an example</a> using a demo certificate. But it's unclear to me how to obtain such a certificate. Using the demo version still doesn't allow me to set the user's rights properly.</p>