D7 发邮件

我的源程序:......
Button1: TButton;
    IdSMTP1: TIdSMTP;
    procedure Button1Click(Sender: TObject);
......
procedure TForm1.Button1Click(Sender: TObject);
begin
    IdSMTP1.Password:='******';
    IdSMTP1.Username:='[email protected]';
    IdSMTP1.QuickSend('smtp.citiz.net','mail','[email protected]','[email protected]','try');
end;
end.运行报错:'Socket Error # 10053 software caused connection aborgt.'不知道是怎么回事,请各位看看,指点一下