Hi @Marina Hinic
Welcome to our forum!
Unfortunately, it's currently not possible to sync Windows 10 taskbar calendars with the new Outlook app. The taskbar calendar only syncs with the Calendar app, which is why you'll be able to see your events there, but not in the new Outlook app.
The new Outlook now replaces the previous mail and calendar applications. You can no longer able to send and receive emails or events using Windows Mail and Calendar. Any local emails, calendar events, and contacts stored in Mail, Calendar, and People will remain exportable following the steps in Export emails and contacts from Windows Mail or People and import to new Outlook.
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