Adding a mailbox to Outlook

If you  have access to another mailbox but it isn't showing up in Outlook, you can manually add it by following these steps.

1. Click File, the Account Settings drop-down menu, and choose Account Settings.
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2. Under the "E-mail" tab, choose your account, and then click Change.
3. Click More Settings..., click the Advanced tab, and then click Add.
4. Type the name of the shared mailbox, and then click OK.
5. Click OK, Next, and Finish.