<IfModule mod_rewrite.c>
  RewriteEngine On
  # !IMPORTANT! Set your RewriteBase
  RewriteBase /
  RewriteCond %{REQUEST_FILENAME} !-f
  RewriteCond %{REQUEST_FILENAME} !-d
  RewriteRule ^(.*)$ index.php?/$1 [L]
</IfModule>

<IfModule !mod_rewrite.c>
  # If we don't have mod_rewrite installed, all 404's
  # can be sent to index.php

  ErrorDocument 404 /index.php
</IfModule>