I INSTALLED VER 7 ON WIN 10. ALL THE TABS APPEAR: CALENDAR, TASKS, CONTACTS, WIDGETS BUT NOT EMAIL! I CAN COMPOSE A MESSAGE AND SEND IT BUT I CANNOT SEE THE MAIL SCREEN. WITH VER 6 I HAVE NO PROBLEMS.
On the vertical control panel (far left), right-click on any of the tabs (e.g., calendar, tasks, etc.) and ensure that “Mail” is checked.