The system and methods of the present application comprise one or more computers that generate and maintain a plurality of software-simulated computers. Each software-simulated computer is adapted to efficiently run an installed application program. Additional security layers provide access to the installed application through a remote user interface installed on a user's computing device. The system generates a new copy of the software-simulated computer for each user session, that prevents configuration problems from interfering with the proper operation of the application program, thereby consistently running the application in an optimized fashion, regardless of changes made to the software-simulated computer by the user or a virus. These software-simulated computers are unaffected by changes a user makes on their own client device. To this end, the system provides robust, web accessible capabilities to application software that may not have been adapted for use on the Internet.