protected function get_error_string($fielderror)
 {
     $premium_local_error_strings = array('pdfemb_mobilewidth|widtherror' => __('Mobile width should be an integer number of pixels, or 0 to turn off', 'pdf-embedder'), 'pdfemb_license_key|tooshort_texterror' => __('License key is too short', 'pdf-embedder'), 'pdfemb_license_key|invalid' => __('License key failed to activate', 'pdf-embedder'), 'pdfemb_license_key|missing' => __('License key does not exist in our system at all', 'pdf-embedder'), 'pdfemb_license_key|item_name_mismatch' => __('License key entered is for the wrong product', 'pdf-embedder'), 'pdfemb_license_key|expired' => __('License key has expired', 'pdf-embedder'), 'pdfemb_license_key|site_inactive' => __('License key is not permitted for this website', 'pdf-embedder'), 'pdfemb_license_key|inactive' => __('License key is not active for this website', 'pdf-embedder'), 'pdfemb_license_key|disabled' => __('License key has been disabled', 'pdf-embedder'), 'pdfemb_license_key|empty' => __('License key was not provided', 'pdf-embedder'));
     if (isset($premium_local_error_strings[$fielderror])) {
         return $premium_local_error_strings[$fielderror];
     }
     return parent::get_error_string($fielderror);
 }