Hi Surya,
I tested the following code in IE9, it works fine. One "'" is missing in your code, you can have a comparison.
<%@ Page Language="C#"%>
<%@ Register TagPrefix="CE" Namespace="CuteEditor" Assembly="CuteEditor" %>
<html>
<head>
<title>JavaScript API</title>
<script language="JavaScript" type="text/javascript" >
function showDialog() {
window.showModalDialog('default.aspx', null, 'status:no;dialogWidth:750px;dialogHeight:507px;dialogHide:true;help:no;scroll:no'); }
</script>
<script runat="server">
override protected void OnInit(EventArgs e)
{
}
</script>
</head>
<body>
<form id="Form1" runat="server">
<CE:Editor id="Editor1" Width="860" runat="server">
</CE:Editor><br />
<p style="width: 580px">
<input type="button" value="showDialog" onclick="showDialog()" id="Button2">
</p>
</form>
</body>
</html>
Thanks for asking