private void WriteRegistry()
{
 string strName = Application.ExecutablePath;
 if (File.Exists(strName))
 {
  string strNewName = Path.GetFileName(strName);
  RegistryKey reg = Registry.LocalMachine.OpenSubKey("SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Run", true);
  if (reg == null)
  {
   reg = Registry.LocalMachine.CreateSubKey("SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Run");
  }
  else
  {
   if (reg.GetValue(strNewName) == null)
   {
    reg.SetValue(strNewName, strName);
   }
  }
 }
}