404 error from codeigniter when hosted to server (tried every possible conditions)

If the .htaccess file you show is in the website's public folder then you should delete the following code

Code:

<IfModule authz_core_module>
    Require all denied
</IfModule>
<IfModule !authz_core_module>
   Deny from all
</IfModule>

You don't want to deny access to the web server, do you?