Hi,
I have checked,It is working fine
Try below code
HTML
<html xmlns="http://www.w3.org/1999/xhtml">
<head runat="server">
<title></title>
<link rel="Stylesheet" type="text/css" href="CSS/uploadify.css" />
<link href="http://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/3.0.3/css/bootstrap.min.css"
rel="stylesheet" type="text/css" />
<script type="text/javascript" src="scripts/jquery-1.3.2.min.js"></script>
<script type="text/javascript" src="http://cdnjs.cloudflare.com/ajax/libs/twitter-bootstrap/3.0.3/js/bootstrap.min.js"></script>
<script type="text/javascript" src="scripts/jquery.uploadify.js"></script>
<script type="text/javascript">
$(window).load(
function () {
$("#<%=FileUpload1.ClientID %>").fileUpload({
'uploader': 'scripts/uploader.swf',
'cancelImg': 'images/cancel.png',
'buttonText': 'Browse Files',
'script': 'Upload.ashx',
'folder': 'uploads',
'fileDesc': 'Image Files',
'fileExt': '*.jpg;*.jpeg;*.gif;*.png',
'multi': true,
'auto': true
});
}
);
</script>
</head>
<body>
<form id="form1" runat="server">
<div style="padding: 40px">
<asp:FileUpload ID="FileUpload1" runat="server" />
</div>
</form>
</body>
</html>