[NumLock]

Код:

type
  TMainForm = class(TForm)
    is_login: Boolean;
    procedure FormCreate(Sender: TObject);
    procedure FormActivate(Sender: TObject);

procedure TMainForm.FormCreate(Sender: TObject);
begin
  is_login:=True;
end;

procedure TMainForm.FormActivate(Sender: TObject);
var
  login_count: Integer;
begin
  if is_login then
  begin
    is_login:=False;
    login_count:=3;
    while (login_count>0) do
    begin
      if FormLogin.ShowModal=mrOk then
      begin
        if (FormLogin.Edit1.Text='admin') and (FormLogin.Edit2.Text='admin') then Exit;
      end else Break;
      Dec(login_count);
    end;
    Close;
  end;
end;