Run control panel's applet

Use WinExec function with one of the parameters: Access.cpl: Accessibility Properties Appwiz.cpl: Add/Remove Programs Properties Desk.cpl: Display Properties Inetcpl.cpl: Internet Properties Intl.cpl: Regional Settings Properties Joy.cpl: Joystick Properties Main.cpl: Mouse Properties Mmsys.cpl: Multimedia Properties Modem.cpl: Modems Properties Netcpl.cpl: Network Properties Odbccp32.cpl: 32 bit ODBC Data Source Administrator Password.cpl: Password Properties Sysdm.cpl: System Properties Themes.cpl: Desktop Themes Timedate.cpl: Time/Date Properties Wgpocpl.cpl: MS Workgroup Post Office

procedure TForm1.Button1Click(Sender: TObject);
begin
  WinExec(
    PChar('rundll32.exe shell32.dll, Control_RunDLL Modem.cpl'),
    SW_SHOWNORMAL);
end;