Give access Calendar entries owned by Internal logged-in User.
Configure the user profile on the Object Settings when the tab is not visible.
Go to Setup > Profile > Standard Platform User / Standard Platform One App User / Standard Platform User > Object Settings > My Calendar > Default On > Save.
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Also, give access to the Apex Classes.
Note: You need to configure the Profile of the User that you want to give access to My Calendar.
In the Standard Platform User profile, go to the Apex Class Access and the following Apex Classes
PosiEd.CalendarController
PosiEd.ColorHexGenerator
PosiEd.CustomCalendarPortalHandler
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You can now check the My Calendar by searching it on the App Launcher.
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To check if the component is working, go to Setup > Users > Look for the staff member (Ex. Michael Aitken) > click Login.
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