When i am trying to download a file whose name has characters from languages like chinese japanese etc...... non ascii... the downloaded file name is garbled. How to rectify it.

I have tried to put charset=UTF-8 in the Content-type header property, but no success. Please help. Code below.

header("Cache-Control: ");// leave blank to avoid IE errors

header("Pragma: ");// leave blank to avoid IE errors

header("Content-type: application/octet-stream");

header("Content-Disposition: attachment; filename=\"".$instance_name."\"");

header("Content-length:".(string)(filesize($fileString)));

sleep(1);

fpassthru($fdl);