I tried this without success
$search = array(’„’, ’“’, ’’’, ’’’, ’,Äô’, ’,Äú’, ’”’, ’“’);
$replace = array(’"’, ’"’, "’", "’", "’", ’"’, ’"’, ’"’);
return trim(htmlentities(str_replace($search, $replace, $str), ENT_QUOTES));
My guess is that ’,Äô’ is not actually a string. It is a representation of an unknown character.
Maybe the export was done using a strange character set. Maybe the file needs to be exported again.
