Kde dělám chybu v tomto příkladě **(tučné písmo v to řádku to vyhazuje chybu za běhu to znamená když kliknu na buton)**
unit Unit1;

interface

uses
Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
Dialogs, IdBaseComponent, IdComponent, IdRawBase, IdRawClient,
IdIcmpClient, StdCtrls;

type
TForm1 = class(TForm)
Ping: TIdIcmpClient;
ListBox1: TListBox;
Button1: TButton;
procedure PingReply(ASender: TComponent;
const AReplyStatus: TReplyStatus);
procedure Button1Click(Sender: TObject);
private
{ Private declarations }
public
{ Public declarations }
end;

var
Form1: TForm1;
lstReplies:Tlistbox;
implementation

{$R *.dfm}

procedure TForm1.PingReply(ASender: TComponent;
const AReplyStatus: TReplyStatus);
var sTime:string;
begin
if (AReplyStatus.MsRoundTripTime=0) then
sTime:='<1'
else
sTime:='=';
lstReplies.Items.Add(Format('%d bytes from %s: icmp_seq=%d ttl=%d time%s%d ms',[AReplyStatus.BytesReceived,AReplyStatus.FromI pAddress,AReplyStatus.SequenceId,AReplyStatus.TimeT oLive,sTime,AReplyStatus.MsRoundTripTime]));
end;
procedure TForm1.Button1Click(Sender: TObject);
var cnt:integer;
begin
Ping.Host:='www.cpress.cz';
for cnt :=1 to 4 do
begin
Ping.Ping;
application.ProcessMessages;
sleep(1000);
end;

end;

end.