$(window).load(function(){
  $('.alertbox').click(function(){
    alert('You Clicked on Click Here Button');
    });
  })

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.0.0/jquery.min.js"></script>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/css/bootstrap.min.css">
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.6/js/bootstrap.min.js"> </script>
  
<div>
  <a class="alertbox" href="#clicked"> Click Here</a>
</div>

Quiero que la alerta se muestre en el modo de arranque.