public function downloadResultFile($sOutputKey = null)
    {
        $sCurrentKey = (empty($sOutputKey)) ? $this->_sOutputKey : $sOutputKey;

        $this->_oUtils = \OxidEsales\Eshop\Core\Registry::getUtils();
        $iFileSize = filesize($this->_oUtils->getCacheFilePath($sCurrentKey));

        $this->_oUtils->setHeader("Pragma: public");
        $this->_oUtils->setHeader("Expires: 0");
        $this->_oUtils->setHeader("Cache-Control: must-revalidate, post-check=0, pre-check=0, private");
        $this->_oUtils->setHeader('Content-Disposition: attachment;filename=' . $this->_sOutputFileName);
        $this->_oUtils->setHeader("Content-Type:text/html;charset=utf-8");
        if ($iFileSize) {
            $this->_oUtils->setHeader("Content-Length: " . $iFileSize);
        }
        echo $this->_oUtils->fromFileCache($sCurrentKey);
    }