title: Only office version changed issue
body: <p>I have download 3.0 source code and run it <code>ubuntu</code> server.
  When I upload existing file or open demo.docx, it renders it and enter to edit mode successfully.</p>
  
  <p>If I modify the docx such as entering some words and closed the web browser after that once gain I open the browser and link to that docx file.
  But it shows <code>"Version changed"</code> error message.
  and I can't edit the docx file any more and I have lost the updated changes of file.</p>
  
  <p>Even though I reload it several times, and tried other files, the prog shows the same error.</p>
  
  <p>Please refer screenshot for error message:</p>
  
  <p><a href="https://i.stack.imgur.com/gOdzZ.png" rel="nofollow"><img src="https://i.stack.imgur.com/gOdzZ.png" alt="enter image description here"></a></p>
  
  <p>Please suggest for this.</p>
  
  <p>Thank you.</p>