To set the Meta Tags in ASP.NET 4 you should use the MetaKeywords and MetaDescription properties which are members of the Page class.

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You can set these properties at run time, so you get the content from a database or other source, and which lets you set the tags dynamically.

You can also set the Keywords and Description properties in the @ Page directive at the top of the Web Forms page:

<%@ Page Language=”C#” AutoEventWireup=”true”
CodeFile=”Default.aspx.cs”
Inherits=”_Default”
Keywords=”some sample keywords”
Description=”Some sample description” %>