using System.Runtime.InteropServices;
 
 
 
  private const int a = 0xF060;
        private const int b = 0x1;
        [DllImport("user32.dll")]
        private static extern IntPtr c(IntPtr hWnd, bool bRevert);
        [DllImport("user32.dll")]
        private static extern int d(IntPtr hMenu, int wIDEnableItem, int wEnable);
 
 
        private void frmmain_Load(object sender, EventArgs e)
        {
            d(c(this.Handle, false), a, b);
        }