Exchange 2025 Public Calendar Not Showing. Typically, the calendar on the mobile device is missing events that appear in microsoft outlook or in outlook web app in exchange online. When the microsoft outlook calendar is not showing holidays in your region, shows wrong dates, or has other outlook holiday issues, we recommend fixing the issue.
First make sure, you have given users correct permission to access the public folder in the exchange admin center > public folders > public folders. When a user tries to access the calendar by using outlook on the web (formerly known as outlook web app), that user receives the following error message:
