title: runtime error 400 VBA
body: <p>I really do not know I am doing wrong.
  Excel was working perfectly fine until it broke in the middle of procedure.
  I have fixed code but right now I have problems with opening excel form.</p>
  
  <p>Every time I open excel workbook runtime error '400' shows up.</p>
  
  <p>I do have this code that makes a mess.</p>
  
  <pre><code>Private Sub Workbook_Open()
  UserForm1.Show
  End Sub
  </code></pre>
  
  <p>Now it also says:</p>
  
  <pre><code>Code execution has been interrupted.
  </code></pre>
  
  <p>Dont you know where the problem might be? 
  Thx</p>