title: Xcode won't remove Derived Files
body: <p>I need to figure out why it is that Xcode, suddenly and with no provocation, starts handing me this error and not allowing me to build my project. When I say, "without provocation", I mean I'm editing text in the database the app delivers text from, and checking my progress in the simulator, doing nothing in Xcode at all except cleaning, building and testing. Everything will be fine for several test sequences, then suddenly, changing nothing in my procedures, the app won't build and I get these errors:</p>
  
  <blockquote>
    <p>error: remove
    /Users/casey-cayce/Library/Developer/Xcode/DerivedData/PEM-LTE-2016-gyoajgqmkkoluhgbrhjmgwakiejl/Build/Products/Debug-iphonesimulator/Living
    the Eucharist.app/images: Directory not empty</p>
    
    <p>error: couldn't remove
    '/Users/casey-cayce/Library/Developer/Xcode/DerivedData/PEM-LTE-2016-gyoajgqmkkoluhgbrhjmgwakiejl/Build/Products/Debug-iphonesimulator/Living
    the Eucharist.app/images' after command failed: Directory not empty</p>
  </blockquote>
  
  <p>I've gone to this Derived Data folder and physically deleted the contents, only to have Xcode restore those contents when I reopen the app, fail the build, then give me the same errors over again. My only solution so far is to completely delete Xcode and the Developer folder, reinstall Xcode, after which it behaves fora little while, but will eventually do the same thing again. I've done this 3 times so far today.</p>
  
  <p>If anyone has any suggestions, please help me get this resolved so I can get this project exported and finished.</p>
  
  <p>Thanks.</p>
  
  <p>Additional info in response to responses:<br><br>
  I have:<br>
  1: Closed the project.<br>
  2: Opened the Projects, folder and deleted the Derived Data, seen the Projects folder go blank (empty) with "No Projects" showing in the window.<br>
  3: Made sure the trash is emptied.<br>
  4: Run "WatchDog," an app developed specifically for dealing with Derived Data issues in XCode.<br>
  5: Closed Xcode &amp; re-opened.<br>
  6: Opened the project, cleaned, and run the Build command.<br>
  <br>
  After all that, the same errors come up again.</p>