title: App crash on iOS 5 - Could not instantiate class named NSLayoutConstraint
body: <p>My app is working very fine on iPhone and Simulator with iOS 6, but when i try to run on iPhone/Simulator with iOS 5 the app crashes</p>
  
  <p>The error is: </p>
  
  <blockquote>
    <p>Terminating app due to uncaught exception 'NSInvalidUnarchiveOperationException', reason: 'Could not instantiate class named NSLayoutConstraint'</p>
  </blockquote>
  
  <p>I'm not using Autolayout on Interface Builder Document.</p>
  
  <p>Could anyone help me?</p>
  
  <p><strong>Autolayout is not checked</strong></p>