thanks for the relpy.
my problem is still not resolved, the ‘categories’ box is checked and i can add them to my menu. the thing is that when i add them in appearance->menus (in the left side), nothing happpens, they don’t show in the menu.
menu items have no parent pages, but ‘categories’ have a parent page.
if only i can put in the menu a link that has a parent page thing which is not possible as ‘/’ between slugs is being deleted when i add it.
thanks.