title: Missing Plug-In When Opening Project in NetBeans
body: <p>I've inherited a java project that appears to have been developed using the NetBeans IDE.</p>
  
  <p>It contains a nbproject subdirectory.</p>
  
  <p>When I try to open the project using NetBeans 6.9 it reports the following error in the Project Name text box:</p>
  
  <pre><code>&lt;unrecognized project; missing plug-in?&gt;
  </code></pre>
  
  <p>How can I determine which plug-in it is looking for?</p>