Codeigniter 3 File Upload Issue

Just a few things I would check.
Is the file of the allowed type? (I had jpg files called file.jpeg which caused an error)
if $config['allowed_types'] case insensitive? What would happen if the file is called file.JPG
Is the file upload limit in php.ini high enough? You set it in the config to 8048 but if in php.ini its still to 2M this will still fail
Is max_post_size in php.ini high enough?

I hope this helps.

On the package it said needs Windows 7 or better. So I installed Linux.