static class Program
    {

        /// <summary>
        /// The main entry point for the application.
        /// </summary>
        [STAThread]
        static void Main()
        {
            try
            {
                const string mutextName = "wwwwwwwwhhhwlllllll77777777ll9999llllwwww";
                Mutex m = new Mutex(true, mutextName);
                bool b = m.WaitOne(TimeSpan.Zero, true);
                MessageBox.Show(b.ToString());
                
                m.ReleaseMutex();
                
                Application.EnableVisualStyles();
                Application.SetCompatibleTextRenderingDefault(false);
                Application.Run(new Form1());
            }
            catch (Exception e)
            {
                MessageBox.Show(e.Message);
            }
        }
    }

Mutex m = new Mutex(true, mutextName);