⤷ 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;
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