Remove index.php from URL in Codeigniter
This is the simple way and it works fine for removing index.php from your url
RewriteEngine onRewriteCond $1 !^(index\.php|uploads|css|js|lib|img|bootstrap|robots\.txt)RewriteRule ^(.*)$ /manage/index.php/$1 [L]instead of manage put your own application folder name.
Use following htaccess code to remove index.php from your codeigniter url
RewriteEngine onRewriteCond $1 !^(index\.php|images|robots\.txt|css)RewriteRule ^(.*)$ ./index.php/$1 [L]
Though your client confirmed the rewrite module is working, what don't you confirm it yourself, make a php file on the root of the project with the code below and try to browse the file.
<?php if( !function_exists('apache_get_modules')){ echo 'Rewrite module not available'; }else{ if(in_array('mod_rewrite',apache_get_modules())) echo 'Rewrite module enabled'; }