uses 
  ComObj; 
 
procedure TForm1.FormCreate(Sender: TObject); 
begin 
  OpenDialog1.Filter := 'TXT / DOC|*.txt;*.doc'; 
  OpenDialog1.Options := [ofHideReadOnly, ofAllowMultiSelect, ofPathMustExist, 
    ofFileMustExist, ofEnableSizing]; 
end; 
 
procedure TForm1.Button1Click(Sender: TObject); 
const 
  wdFormatRTF = 6; 
var 
  x: integer; 
  s: string; 
  Word1: Variant; 
begin 
  try 
    Word1 := CreateOleObject('Word.Application'); 
  except 
    raise exception.create('MS-Word ist nicht ansprechbar! '); 
    exit; 
  end; 
  Button1.enabled := false; 
  try 
    if OpenDialog1.execute then 
    begin 
      Screen.cursor := crHourglass; 
      for x := 0 to OpenDialog1.Files.count - 1 do 
      begin 
        s := ExtractFilename(OpenDialog1.Files[x]); 
        s := ChangeFileExt(s, '.rtf'); 
        Word1.Documents.Open(OpenDialog1.Files[x]); 
        Word1.ActiveDocument.SaveAs(s, wdFormatRTF); 
        Word1.Documents.close; 
      end; 
      Word1.Quit; 
    end; 
  except 
    raise exception.create('Unerwarteter Fehler'); 
  end; 
  Button1.enabled := true; 
  Screen.cursor := crDefault; 
end;