请SOAP高手解答！

Question

中间层源码：
function TSvr.getInfo(...): TSOAPAttachment; 
var
  attach: TSOAPAttachment;
  Query: TAdoquery;
  Connection1: TADOConnection;
  sTmp: string;
begin
  Result := nil;
  try
    try
      Connection1 := TADOConnection.Create(nil);
      Connection1.LoginPrompt := false;
      Connection1.ConnectionString := sConn;
      Connection1.Open;
      query := tadoquery.Create(nil);
      Query.Connection := Connection1;
      with Query do
      begin
        sTmp := 'Select ...';
        SQL.Text := sTmp;
        Prepared;
        Open();
      end;
    except
      raise ERemotableException.Create('数据库连接错误2' + sTmp);
      exit;
    end;
    attach := ADOQuery2Attachment(query);
    if attach = nil then
    begin
      raise ERemotableException.Create('数据转换错误');
      exit;
    end;
    Result := attach;
  finally
  {  query.Close;
    connection.Close;
    query.Free;
    connection.Free;  }
  end;
end;function ADOQuery2Attachment(query: TADOQuery): TSOAPAttachment;
var
  buf: array[0..255] of AnsiChar;
  tempfile, zippedfile: string;
  z: TZippor;
  attach: TSOAPAttachment;
  mem: TMemoryStream;
begin
  Result := nil;  if query = nil then exit;  if not query.Active then exit;  GetTempPath(256, buf);
  GetTempFileName(buf, 'TTC' + chr(0), 0, buf);
  tempfile := string(buf);
－－－－－－－－－－－－－－－－－－－1
  query.SaveToFile(tempfile);
－－－－－－－－－－－－－－－－－－－1
  try
    z := TZippor.Create;
    try
      GetTempPath(256, buf);
      GetTempFileName(buf, 'TTC' + chr(0), 0, buf);
      zippedfile := string(buf);
      z.CompressFile(tempfile, zippedfile);
      raise ERemotableException.Create('数据库连接错误3');
      try
        mem := TMemoryStream.Create;
        mem.LoadFromFile(zippedfile);        attach := TSOAPAttachment.Create;
        attach.SetSourceStream(mem);
        raise ERemotableException.Create('数据库连接错误4');
        Result := attach;      finally
        DeleteFile(zippedfile);
      end;
    finally
      z.Free;
    end;  finally
    DeleteFile(tempfile);
  end;end;
上面的代码是用于传输数据集的，但在执行到query.SaveToFile(tempfile);
时出错，就是保存不了，提示什么"%1已经存在！"
请各位高手赐教！！！