Codeigniter default routing doesn't work

Question

In my new CI project, I am getting the following error every time I try to access any URL other than the base url and the base url /index.php. For example, if I'd like to access the "about" page:

Not Found

The requested URL /my_base_url/about was not found on this server.

This is what my routes.php file looks like:

$route['default_controller'] = "base";
$route['about'] = "base/about";
$route['404_override'] = '';

I've triple checked my Base controller and it definitely has an about method (which loads an existing "about" view).

Here's my .htaccess file:

RewriteEngine on
RewriteCond $1 !^(index\.php|images|robots\.txt)
RewriteRule ^(.*)$ /index.php/$1 [L]

And here's a few things I've set in my config.php file:

$config['base_url'] = 'http://localhost/my_base_url/';
$config['index_page'] = '';
$config['uri_protocol'] = 'AUTO';

What am I doing wrong? Any help much appreciated!

Solution

The htaccess file should be in the my_base_url directory, and you should include a rewrite base:

Options FollowSymLinks

RewriteEngine on
RewriteBase /my_base_url/
RewriteCond $1 !^(index\.php|images|robots\.txt)
RewriteRule ^(.*)$ index.php/$1 [L]