When i upload file type 'rar' in CodeIgniter, there is a problem when upload. It showed warning : The filetype you are attempting to upload is not allowed.

The solution is quite simple, just edit in this file : services\application\config\mimes.php
add 1 line in $mimes array : 'rar'    =>    'application/octet-stream',

I think other file type will have that error too if it does not list at mimes.