title: Xcode 4.5: NSLayoutConstraint issue in iphone 5.1 simulator
body: <p><strong>I am getting an error</strong>:</p>
  
  <p><code>Terminating app due to uncaught exception 'NSInvalidUnarchiveOperationException', reason:</code></p>
  
  <pre><code>'Could not instantiate class named NSLayoutConstraint'
  </code></pre>
  
  <p>when I am trying to run my application in <strong>iPhone 5.1 simulator</strong>. It works fine on my iOS 6.0 and 5.0 Simulator and on my device too. It crashed before it runs the app, actually it crashes on the splash screen. Trying to delete the app doesn't work. It cant be deleted from the device, so I deleted it from <em>/User/"name"/library/application support/simulator/my app</em>. If I touch the X in the simulator it freezes. "<code>Autolayout</code>" is <strong>unchecked</strong>, otherwise it would not run at all. 
  Do have anyone suggestions what to do now? </p>