title: app preview disappears after changing the poster frame
body: <p><em>Hey guys, I have a problem with uploading my app preview. This occurs every time I try to upload the app preview. I written down the problem in systematical text.</em></p>
  
  <p><strong>What I did with the app preview:</strong></p>
  
  <ul>
  <li>Made my app preview in Imovie and compiled it in 4k resolution with a low quality.</li>
  <li>Seeing this article and followed the first answer: <a href="https://stackoverflow.com/questions/25820601/unable-to-load-app-preview-in-itunes-connect">Unable to load app preview in iTunes connect</a></li>
  </ul>
  
  <p><strong>What works:</strong></p>
  
  <ul>
  <li><p>Saving the app preview in iTunes Connect.</p></li>
  <li><p>Processing the app preview.</p></li>
  <li><p>Changing the poster frame from the app preview.</p></li>
  </ul>
  
  <p><strong>What not works:</strong></p>
  
  <ul>
  <li>Saving the app preview again after changing the poster frame.</li>
  </ul>
  
  <p><strong>What happens:</strong></p>
  
  <ul>
  <li>The app preview is disappeared, and removed from iTunes Connect.</li>
  <li>I never get any errors like most people get.</li>
  </ul>
  
  <p><strong>More information:</strong></p>
  
  <ul>
  <li>Running Safari version: 9.1.2 </li>
  <li>Running OS X version: 10.11.6</li>
  </ul>