apache - Codeigniter 3 Remove index.php Problems

Question

I have a little project that i developed for a client in codeigniter 2.1.4 and now, he insists to migrate to codeigniter 3 DEV version. I know that's not a good ideea but... My problem is that i can't remove the index.php from the url.

This is my .htaccess file :

  Options +FollowSymLinks
  RewriteEngine on

  # Send request via index.php
  RewriteCond %{REQUEST_FILENAME} !-f
  RewriteCond %{REQUEST_FILENAME} !-d
  RewriteRule ^(.*)$ index.php?/$1 [L]

I have removed the index.php from the config.php file
No luck
I reinstalled the LAMP server (i'm on Ubuntu 12.04'), reconfigured
I have other projects on my local server developed on Codeigniter 2.1.4 and Laravel 4 and they work just fine but this one it's killing me.
Thank you!

Answer 1

I made this way:

Created the .htaccess in the root folder of the project with the content:

RewriteEngine on
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond $1 !^(index.php|css|js|images|robots.txt)
RewriteRule ^(.*)$ index.php?$1 [L]

Then, in the config.php i modified this line.

From:

$config['url_suffix'] = 'index.php';

To:

$config['url_suffix'] = '';