title: "Unknown class in Interface Builder file" for known existing VC
body: <p>I am building an app in Xcode 4.6.2 . Everything was working fine until I added a storyboard from a previous version of the project, cut and pasted a view from the old storyboard and then deleted the old storyboard. No I am getting "Unknown class <em>nameOfAnActualClassinMyProject</em> in Intefrace Builder File" . This class a viewController but not the ViewController for the view I just pasted in. I have read alot of questions and answers on this topic and have unsuccessfully made many attempts to fix this. Also I am not using the simulator for this project only the actual iphone.</p>
  
  <ul>
  <li>Looked for any inappropriate references in storyboard</li>
  <li>I have cleaned the app and then built it again</li>
  <li>I have deleted the app from the phone </li>
  <li>I have deleted the file which seems to be causing the problem and added it back in.</li>
  <li>I have reset the phone and reprovisioned (I read one answer where the problem had to do with old files in the simulator.</li>
  </ul>
  
  <p>Also the view from the unknown view controller seems to correctly display.</p>
  
  <p>The app doesn't crash however it displays a warning in the output log. Any help would be appreciated.
  thanks.</p>