Restrict access to non-wordpress section of site with user roles?

if you can include the wp-load.php from WP install; after this you can use all WP Core functions and can also check the user and his rights with core function – current_user_can().

But maybe it’s easier to create an bridge from CS Cart to WP, if CS Cart has an own user table; i dont know.

Hata!: SQLSTATE[HY000] [1045] Access denied for user 'divattrend_liink'@'localhost' (using password: YES)