title: Cannot select checkbox in a databounded DataGridView
body: <p>I've a DataGridView which is working perfectly fine. I use it just to show data. </p>
  
  <p>Now I want ability to select rows by check box and perform an operation for only selected rows on click of a button (this button is out of the grid on the same form). 
  For this purpose, I'm following <a href="https://stackoverflow.com/questions/1035102/help-with-adding-checkbox-column-to-datagridview-in-window-form/1039955#1039955">these</a> steps to add checkbox column to datagridview. </p>
  
  <p>On running the application what is see is I can't check the check box either by mouse click or keyboard. And by its looks I can understand that its not in disabled/readonly state. So whenever I try to click on the checkbox, it changes it's borders normally as an enabled check box does. But finally it is not checking the check box.</p>