Посмотрите пожалуйста, может стоит что-то дополнить? мой файл .htaccess
Options +FollowSymlinks
# Prevent Directoy listing
Options -Indexes
# Prevent Direct Access to files
<FilesMatch "(?i)((\.tpl|\.ini|\.log|(?<!robots)\.txt))">
Order deny,allow
Deny from all
</FilesMatch>
# SEO URL Settings
RewriteEngine On
# If your opencart installation does not run on the main web folder make sure you folder it does run in ie. / becomes /shop/
RewriteBase /
RewriteRule ^sitemap.xml$ index.php?route=feed/google_sitemap [L]
RewriteRule ^googlebase.xml$ index.php?route=feed/google_base [L]
RewriteRule ^system/download/(.*) index.php?route=error/not_found [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteCond %{REQUEST_URI} !.*\.(ico|gif|jpg|jpeg|png|js|css)
RewriteRule ^([^?]*) index.php?_route_=$1 [L,QSA]
RewriteEngine On
RewriteCond %{HTTP_HOST} ^www.сайт.ru$ [NC]
RewriteRule ^(.*)$ http://сайт.ru/$1 [R=301,L]
RewriteCond %{THE_REQUEST} ^[A-Z]{3,9}\ /index\ HTTP/
RewriteRule ^index\.html$ / [R=301,L]
RewriteCond %{THE_REQUEST} ^[A-Z]{3,9}\ /index\.php\ HTTP/
RewriteRule ^index\.php$ / [R=301,L]
RewriteCond %{QUERY_STRING} ^route=common/home$
RewriteCond %{REQUEST_METHOD} !^POST$
RewriteRule ^index\.php$ http://%{HTTP_HOST}? [R=301,L]