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Adding a shared mailbox to new Outlook
Open Outlook (New).
Hover your mouse over the Shared with me folder in the left navigation pane. A button with three dots will pop up. Clicking on this button will Hover your mouse overclick on the three dots and then choose Add shared folder or mailbox.
In the Add shared folder or mailbox. dialog box, type the name or email address of the shared mailbox, and then click Add.
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