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Move Calendar Entries
Open up 2 Outlook windows - you are going to drag and drop calendar appointments from one window to another.Open up the calendar you just created on the right side of your monitor. It , you will find it is under My Calendars.
Navigate down in the list of calendars to your shared mailbox calendar that you want the calendar to be moved to, then right click on it and select Open in New Window. Another Outlook window session will appear. Move it over to the left side of your monitor; Open in a New Window is NOT an option in Outlook 2021, so simply start another session of Outlook, navigate to the shared calendar and move it to the left of your current Outlook session.
On the right Outlook session window, click view View in the toolbar then select the panel Change View and choose List. This will list all of the calendar entries. If you don’t want to import all items you could sort by date and only import some of them.
Choose the items to import. if it is all of them, quickly select them all by hitting To Select all items use the Ctrl + A buttons on your keyboard . Click then click and drag the items you selected from right session to left session and drop them into your new shared mailbox. Outlook will then copy all the items in to into the new shared calendar.
Almost Done
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