For .NET 1.1, The VS.NET solution is SpringAir.2003.sln In order to be able to run SpringAir you will need to create 'SpringAir.2003' virtual directory using IIS Administrator and point it to the following directory : examples\Spring\SpringAir\src\SpringAir.Web.2003 For .NET 2.0, The VS.NET solution is SpringAir.2005.sln Set your startup project as SpringAir.Web and the start page to .\Web\Home.aspx If you run .NET 2.0 first and then .NET 1.1, run the nant target 'clean-objs' to remove the object files before starting vs.net 2003 Or do a clean build from vs.net 2005 before starting vs.net 2003.