Dual core appears to the OS as dual CPU, there is a procedure for changing the OS setting to support this feature (unless it was installed on a dual cpu or HT system with HT enabled), but the best way is to re-instyall the OS. Any way the application should work well without special regard accept writing the code in threades (and not to many opening and closing) and using sync features such as mutex and semaphores. Good luck:-D NS