The biggest change was the introduction of a managed code development environment using the. NET (VS.NET), codenamed Rainier (for Washington's Mount Rainier), in February 2002 (the beta version was released via Microsoft Developer Network in 2001). Version 6.0 (codenamed Aspen, after the ski resort in Colorado), was released in June 1998 and is the last version to run on the Windows 9x platform. For more details and user comments, view the versions of this application Version