static void Main()
        {
            bool newMutexCreated = true;
            using (new Mutex(true, Assembly.GetExecutingAssembly().FullName, out newMutexCreated)){
                if (!newMutexCreated) //exist
                    return;
                Application.EnableVisualStyles();
                Application.SetCompatibleTextRenderingDefault(false);
                Application.Run(new ServiceForm());
            }
        }