title: unable to sort or filter data on a protected sheet with locked cells
body: <p>I have a sheet which is protected with locked cells. Even after checking the "sort" and "Auto filter" option while protecting the sheet, I am still unable to sort/filter the data.</p>
  
  <p>I get the following message when I click the Sort button:</p>
  
  <blockquote>
    <p>The cell or chart that you are trying to change is protected and
    therefore read-only. To modify a protected cell or chart, first remove
    protection...</p>
  </blockquote>
  
  <p>Am I missing something?</p>
  
  <p>Thanks in advance</p>