I understand that I can zip multiple file and download it as zip when the files are already exists on ther server. like this. My question is, I have a dropdown list that prompt user download different section of a big form on the fly so I have header below for download it individually. header("Content-type: text/plain"); header("Content-Disposition: attachment; filename=op_summary.lyx"); I need to add another function to download them all at ones. How can I implement it? Should I have download them in the server before zipping it and download to client? I will also need a checkbox fundtion that pick multiple files according whichever files that user select. Any suggestion will be helpful.