No, Eureka's Ultimate Mahjongg does not work on Windows 7 because it is not compatible with this version of Windows. The application was designed to work on Windows 98, ME, 2000, XP or VISTA. This means that you can use Troubleshoot compatibility when you right click the executable/installation file. Activate the option then follow the on-screen instructions. Alternatively, install XP Mode then run the application with XP virtual compatibility mode.