private void button1_Click(object sender, EventArgs e)
   {
       rdp.Server = txtServer.Text;
       rdp.UserName = txtUserName.Text;
       IMsTscNonScriptable secured = (IMsTscNonScriptable)rdp.GetOcx();
       secured.ClearTextPassword = txtPassword.Text;
       rdp.Connect();
   }
   private void button2_Click(object sender, EventArgs e)
       rdp.Disconnect();
   }
}