If you have redirect 301 in htaccess file this module don't work

<IfModule mod_rewrite.c>
RewriteEngine on
RewriteBase /
RewriteCond %{THE_REQUEST} ^[A-Z]{3,9}\ /index\.php\ HTTP/
RewriteRule ^index\.php$ http://site.com/ [R=301,L]
</IfModule>