DotNetNuke is a popular web content management system (or CMS) for Microsoft ASP.NET. The flexible DotNetNuke open source CMS platform also functions as a web application development framework. It is available in both a free Community Edition as well as cost basis Professional and Enterprise editions.
Requires Microsoft IIS, Microsoft SQL Server 2005 or 2008, .net Framework 3.5 sp1 OR 4.0
