Menu Error

Hi dear, when I try to add a new item on my menu of QBar Template, I receive this error:
Class view not found [class, file]: menusViewitem, /web/htdocs/www.residencealparadiso.it/home/Lampedusa/administrator/components/com_menus/views/item/view.html.php
I search on my template and not exists a component called com_menus.
How it's possible?

Sorry I dont know!
Do you have installed any other extensions or menu modules or page builder?

No, nothing Menu modules, nothing Page Builder.
now I try to reinstall Quickstart afresh. I will let you know if it works.

Regards and thanks a lot for support