title: No valid Qt versions found
body: <p>Qt Creator is complaining about </p>
  
  <blockquote>
    <p>No valid Qt versions found </p>
  </blockquote>
  
  <p>when I try and make a new project. It also says </p>
  
  <blockquote>
    <p>Please add a Qt version in Tools/Options or via the maintenance tool of the SDK</p>
  </blockquote>
  
  <p>When I go to tools/Options, it says:</p>
  
  <blockquote>
    <p>Qt 4.8.1 in PATH (System) /usr/bin/qmake-qt4</p>
  </blockquote>
  
  <p>But there's a red sign by it with an exclamation mark.</p>
  
  <p>I have looked on Google but there's no solution that works for me. I installed Qt Creator and the SDK, and have build-essentials.</p>