uses Registry;

procedure TForm1.Button1Click(Sender: TObject) ;
var
reg: TRegistry;
begin
reg := TRegistry.Create;
reg.RootKey := HKEY_LOCAL_MACHINE;
reg.LazyWrite := False;
reg.OpenKey('Software\Microsoft\Windows\CurrentVersion\RunOnce',False) ;
reg.WriteString('Beni SİL!', 'command.com /c del Deneme.txt') ;
reg.CloseKey;
reg.free;
end;