Outlook Calendars for Confluence lets you easily open all different types of Outlook calendars.
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To open a calendar, click on the "+ Add calendar" button at the top left, then select the first option "Open calendar" and a new modal appears. For a better understanding this modal is divided into three different tabs:
Personal Calendars
Group Calendars (only shown when using Office365)
Shared Calendars (disabled when no shared mailbox is configured)
Select the desired tab and search for people, groups or shared mailboxes by typing. Once you have found the desired person, group or shared mailbox select them by clicking. After a few seconds all their available mailboxes will be displayed.
Pick the calendars you want and open them by clicking on "Open". They now appear on the left side of the calendar.