To add a MasterPage to an existing project, make the existing form Page tag look like this.
<%@ Page Language="C#" MasterPageFile="~/MasterPage.master" AutoEventWireup="false" CodeFile="Default.aspx.C#" Inherits="_Default" title="Untitled Page" %>
<
asp:Content ID="Content1" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server"></
asp:Content><div>
This is the home page</div>
Add the MasterPageFile="~/MasterPage.master" attribute
Then remove the following lines from the top:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"><
HTML> <HEAD> <title>CustMain2</title> <meta name="GENERATOR" content="Microsoft Visual Studio .NET 7.1"> <meta name="CODE_LANGUAGE" content="Visual Basic .NET 7.1"> <meta name="vs_defaultClientScript" content="JavaScript"> <meta name="vs_targetSchema" content="http://schemas.microsoft.com/intellisense/ie5"> </HEAD> <body> <form id="Form1" method="post" runat="server">Also remove the following lines from the bottom:
</form>
</body></
HTML>
<
asp:Content ID="Content1" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server"></
asp:Content> <div>This is the home page
</div>