$_FILES -- $HTTP_POST_FILES [deprecated] — HTTP File Upload variables need to access the error param of file1 as, eg $_Files['download']['error']['file1'].
Rather I have fixed the add and delete/remove options also for multiple files upload in PHP. Project code download link and demo link is at the bottom of the
This demo page shows a group of PHP file and directory functions: file upload and download, open a directory, showing the uploaded files in a select menu.