Don't forget to set margins in your body tag.
<html>
<head>
<title>webpage title</title>
</head>
<body bgcolor="#ffffff" leftmargin="0" marginwidth="0" topmargin="0" marginheight="0">
</body>
</html>
with CSS:
<style type="text/css">
body
{
margin: 0px 0px 0px 0px;
padding: 0px 0px 0px 0px;
}
</style>
