This function intercepts Windows logoff messages (WM_QUERYENDSESSION and WM_ENDSESSION) to Visual FoxPro and specifies whether to keep Visual FoxPro COM Server instances running or to shut them down. A Visual FoxPro application will terminate when the current user logs off Windows. If the application is a Windows Service, then that service will terminate. Enabling support for NT service will make it possible for Visual FoxPro applications to continue even if the current user logs off Windows.