When I try to create the Home item for the menu on the Home-Page of my site, it isn't possible. I receive this warning message:
"Save failed with the following error: Another menu item has the same alias in Root (remember it may be a trashed item). Root is the top level parent."
I have 2 more items registered in that menu (with linked single articles), and these two items are displayed correctly in the front-page of my website.
SOLVED: It's only possible to register one unique Home item menu (with unique item alias at current level) for all the set of the items registered at that moment in out Joomla site.
Book "Using Joomla: Building Powerful and Efficient Web Sites", Menu Item Manager, page 83