How can I delete a user menu in Drupal 7? It throws me an access denied error, though I am logged in as user #1. What's wrong with it?
You cannot delete any of the following menus; they come with the core. You can delete any menu you created yourself.
To disable them from displaying go to admin/structure/block.
maybe swithing for another source for secondary links at admin/structure/menu/settings is enough ?
depending on theme you are using: go to theme's .info file and delete secondary links feature // change theme settings