title: Xcode: Can't create snapshot - This file does not exist in the index
body: <p>I am trying to create a snapshot in Xcode 4, and I keep on getting the error "This file does not exist in the index." and it says it can't create a snapshot. When I press ok, it has the progress bar for creating a snapshot and doesn't do anything else.</p>
  
  <p><img src="https://i.stack.imgur.com/GezpM.png" alt="Error dialog"></p>