A system and method that provides a platform-neutral shell application for a user interface is provided. The platform neutral shell application is performed in a way that prevents the user from accessing the underlying operating system. The desktop shell application executes in a middleware application. The operating system residing on the client computer system is booted. The middleware application is loaded on the operating system platform. The middleware application is programmed for the particular operating system being used by the client. The shell application is loaded on the middleware application. The shell application prevents the user from accessing the underlying operating system by maximizing the window in which the shell application is running, pinning the shell application window to the foreground, and removing controls from the desktop window would otherwise allow the user to bypass the desktop shell.