问提交https时的Indy 9 403错误

EN

 `unit MWSDemo;`

interface

uses
  Windows, Messages, SysUtils, Variants, Classes, Graphics, Controls, Forms,
  Dialogs, StdCtrls, HTTPApp, IdBaseComponent, IdComponent,
  IdTCPConnection, IdTCPClient, IdHTTP, IdIOHandler, IdIOHandlerSocket,
  IdSSLOpenSSL, IdServerIOHandler, IdAntiFreezeBase, IdAntiFreeze,
  IdMultipartFormData;

type
  TForm1 = class(TForm)
  Button1: TButton;
  HTTPS: TIdHTTP;
  IdAntiFreeze1: TIdAntiFreeze;
  IdServerIOHandlerSSL1: TIdServerIOHandlerSSL;
  IdSSLIOHandlerSocket1: TIdSSLIOHandlerSocket;
  Memo1: TMemo;
  procedure Button1Click(Sender: TObject);

  private
    { Private declarations }
  public
    { Public declarations }
  end;

var
  Form1: TForm1;

implementation

{$R *.dfm}
uses hash, hmac, sha256, mem_util;

function GetMWSRequest : string;
var
  ctx: THMAC_Context;
   < more code here>
var
  UTC: TSystemTime;
begin
  GetSystemTime(UTC);
  AmazonTimestamp:=HTTPDecode(Format('%.2d', [UTC.wYear]) + '-' 
    + Format('%.2d',         [UTC.wMonth]) + '-' +  Format('%.2d', [UTC.wDay]) + 'T'
    + Format('%.2d', [UTC.wHour]) + ':' + Format('%.2d',  [UTC.wMinute]) + ':' + 
    Format('%.2d', [UTC.wSecond]) + 'Z');
  AmazonURL:='https://mws.amazonservices.com/?';
      < more code here>
  Result:=AmazonURL;
end;

procedure TForm1.Button1Click(Sender: TObject);
var URL, Response: string;
    Stream : TStringStream;
    Params: TIdMultipartFormDataStream;
begin
  URL := GetMWSRequest;
  HTTPS.Request.BasicAuthentication := true;
  HTTPS.Request.ContentType := 'text/html';
  IdSSLIOHandlerSocket1.SSLOptions.Method := TIdSSLVersion(sslvSSLv23);
  HTTPS.IOHandler := IdSSLIOHandlerSocket1;
  try
      Stream := TStringStream.Create('');
      Params := TIdMultipartFormDataStream.Create;
      Params.AddFile('File1', 'UploadData.txt','application/octet-stream');
    try
      HTTPS.Post(URL, Params, Stream);
      Memo2.Text := HTTPS.ResponseText;
    finally
      Stream.Free;
      Params.Free;
    end;
  except
       on E: Exception do
         ShowMessage('** Error: ' + e.Message);
  end;
end;

end.