title: Windows phone 8 App with 7.1 reference
body: <blockquote>
    <p><strong>Possible Duplicate:</strong><br>
    <a href="https://stackoverflow.com/questions/13698094/referencing-zxing-net-library">Referencing ZXing.Net library</a>  </p>
  </blockquote>
  
  
  
  <p>I'm developing an application that targetting Windows phone 8.0 OS
  When I try to add a reference of version (7.1) to the application , </p>
  
  <p>it gives the following error message:</p>
  
  <blockquote>
    <p>A reference to a higher version or incompatible assembly cannot be
    added to the project</p>
  </blockquote>
  
  <p>Why?</p>