I have the basic version of eM Client and I’m not able to view or access my Calendar data. Calendar is no longer visible in the main window menu. Only MAIL, CONTACTS and TASKS is displayed. What happened to CALENDAR? 

Maybe its disabled?
Right-Click on the remaining items in the main menu. Is there the calendar? Is it checked or unchecked?

Da, how numb could I be :)  It was ‘disabled’. Thank you so much.