Salut,





IMPLEMENTATION
{$R *.dfm}

var  HandleMutex : THandle;

function ExecuteDeja : Boolean;
begin
SetLastError(NO_ERROR);
result := true;
if OpenMutex(MUTEX_ALL_ACCESS, false,
                  pChar(ExtractFileName(Application.ExeName))) <>0 then exit;
HandleMutex := CreateMutex(Nil, true,
                                       pChar(ExtractFileName(Application.ExeName)));
if HandleMutex = 0 then exit;
result := false;
end;

procedure TForm1.FormCreate(Sender: TObject);
begin
if ExecuteDeja then Halt;
end;

procedure TForm1.FormClose(Sender: TObject; var Action: TCloseAction);
begin
if HandleMutex <> 0 then ReleaseMutex(HandleMutex);
end;
END.