title: UIDocumentInteractionController causes unknown app identifier com.apple.mobilemail failed error
body: <p>I am getting the following error just after I press one of the document interaction controller buttons i.e. copy, print etc:</p>
  
  <pre><code>Launch Services: Registering unknown app identifier com.apple.mobilemail failed
  Launch Services: Unable to find app identifier com.apple.mobilemail
  </code></pre>
  
  <p>Here is the code that creates the interaction controller - the URL etc is all valid however the delegate calls don't hit my controller even though I have implemented the delegate methods which is weird:</p>
  
  <pre><code>UIDocumentInteractionController *documentInteractionController = [UIDocumentInteractionController interactionControllerWithURL:fileURL];
  documentInteractionController.delegate = self;
  [documentInteractionController presentOptionsMenuFromRect:self.view.bounds
                                                                  inView:self.view
                                                                animated:YES];
  
  //None of these delegate methods are ever called which is weird:
  - (void) documentInteractionController: (UIDocumentInteractionController *) controller
           willBeginSendingToApplication: (NSString *) application
  {
      DebugLog(@"skldjfklsdjflksdjflsdk %@", application);
  }
  
  
  
  - (void) documentInteractionController: (UIDocumentInteractionController *) controller
              didEndSendingToApplication: (NSString *) application
  {
      DebugLog(@"skldjfklsdjflksdjflsdk %@", application);    
  }
  
  - (void)documentInteractionControllerDidDismissOptionsMenu:(UIDocumentInteractionController *)controller
  {
  
  }
  
  - (void)documentInteractionControllerDidDismissOpenInMenu:(UIDocumentInteractionController *)controller
  {
  
  }
  </code></pre>