I try to upload a .pptx file to my server folder named "lesson" and copy that file from the same folder and rename that copied file with .odp extension.
I used ViewerJS plugin and it really work nicely when i open a pdf file.

However. my problem is that when i try to link the .odp file, ViewerJS doesnt finish loading. How can I solve this? Please help

Heres my code for tranforming the copied .pptx file to .odp. file

$oldname = $file;
$newname = basename($file,".pptx");
$n = $newname.".odp";
copy("lesson/".$oldname,"lesson/".$n);

Do you know any free plugins so that i can view an office documents on my website offline?

commented: For that I google that question. Too many today. +0