title: Make a list item Non editable once the Issue status is set to "Closed"
body: <p>I have a SharePoint list to store list items to track an issue. There is a drop down called "Issue Status" which has values - "Active", "In-Progress" &amp; "Closed".</p>
  
  <p>I need help in making the list item non editable when the issue is marked as "<strong>Closed</strong>" in the drop down.</p>
  
  <p>Also a help on making the drop down show only "<strong>Active</strong>" when the new list item is created would be highly appreciated. Thank you.</p>