Gimana Cara Menhghilangkan Index.Php

coba baca di user_guide/general/urls.html di user guidenya deh:
Silahkan diartikan sendiri.

Removing the index.php file

By default, the index.php file will be included in your URLs:
example.com/index.php/news/article/my_article

You can easily remove this file by using a .htaccess file with some simple rules. Here is an example of such a file, using the "negative" method in which everything is redirected except the specified items:
RewriteEngine on
RewriteCond $1 !^(index\.php|images|robots\.txt)
RewriteRule ^(.*)$ /index.php/$1 [L]

In the above example, any HTTP request other than those for index.php, images, and robots.txt is treated as a request for your index.php file.

coba edit file application/config/config.php

.
.
.
/*
|--------------------------------------------------------------------------
| Index File
|--------------------------------------------------------------------------
|
| Typically this will be your index.php file, unless you've renamed it to
| something else. If you are using mod_rewrite to remove the page set this
| variable so that it is blank.
|
*/
$config['index_page'] = "index.php";//ini yg diedit
.
.
.