modalerror.php

 <!-- Modal -->
  <div class="modal fade" id="myModal" role="dialog">
    <div class="modal-dialog">
    
      <!-- Modal content-->
      <div class="modal-content">
        <div class="modal-header">
          <button type="button" class="close" data-dismiss="modal">&times;</button>
          <h4 class="modal-title">Modal Header</h4>
        </div>
        <div class="modal-body">
          <p>Some text in the modal.</p>
        </div>
        <div class="modal-footer">
          <button type="button" class="btn btn-default" data-dismiss="modal">Close</button>
        </div>
      </div>
      
    </div>
  </div>
  
</div>

<script>
$(document).ready(function(){
    $("#myBtn").click(function(){
        $("#myModal").modal();
    });
});
</script>