Comment the branching statement that that clears the listbox.Add a line to clear the listbox immediately before the loop that adds each item.'(VB: beginning around line 129)ListBox1.Items.Clear() '**move this before the loopFor Each item As String In arrayList ' If the ScriptManager is not in an asynchronous postback, then the page is in initial load. ' We therefore add the current item to DropDownList1 since it has not yet been populated. ' Otherwise, we skip this step and clear ListBox1 since that control will be re-populated with ' the query results (i.e. features that intersect the new extent) '**Comment the branching statement below** 'If (Not ScriptManager1.IsInAsyncPostBack) Then ' DropDownList1.Items.Add(item) 'Else ' ListBox1.Items.Clear() 'End If ' Add the current item to the listbox ListBox1.Items.Add(item)Next item