Opening a Shared Folder or Mailbox in Outlook for Mac

From this Microsoft Support article

Method 1: Open Other User's Folder

  • This method is best used when you only have to open one main folder that is shared with you, such as the Inbox, Calendar, or Address Book.
  • To open the shared folder, click Open on the File menu, and then click Other User's Folder.

 

Method 2: Add the mailbox under People I am a Delegate for

  • This method is best used when you are a delegate for another user's mailbox or when you have permissions to several folders in a shared mailbox.
  • This method can also be used when you have full access permissions to a mailbox.
  • To open the shared mailbox, click Accounts on the Tools menu, click Advanced, and then click Delegates. Add the mailbox under People I am a delegate for.



    Note If you have permissions to custom folders in the mailbox but not to the top-level mailbox folder, the custom folders will not appear in the folder list. Only default folders that you have permissions to, such as Inbox, Sent Items, Deleted Items, and Calendar, will appear in the folder list without top-level mailbox folder permissions.
 

Method 3: Add an additional Exchange account by using your own credentials

  • This method is best used when you have full access permissions to a shared mailbox.
  • This method can also be used when you have permissions to the top-level folder of the mailbox and to several subfolders.
  • To open the shared mailbox, click Accounts on the Tools menu. Click the Plus Sign to add an additional Exchange account. Enter the shared mailbox in the E-mail address field, and then enter your own credentials under Authentication.


Notes:
  • When you use any of these methods, the shared mailbox account is added as an option in the From field when you compose emails. This lets you select the account in the From field regardless of whether you have permissions to send from this account. If you do not have "Send As" or "Send On Behalf of" permissions for the account, email from the account will not be sent.
  • Outlook for Mac does not support Auto-mapping of shared mailboxes.

The following table summarizes the permissions options that may be available for a shared folder or mailbox, and the best method for opening the shared folder or mailbox based on the corresponding permission.
Permission to shared folder or shared mailbox Best method to open shared folder or mailbox
Permission to the Inbox, Calendar or Address Book Open Other User's Folder.
Delegate permission to a mailbox Add the mailbox under "People I am a Delegate for."
Permission to several default folders in a mailbox Add the mailbox under "People I am a Delegate for."
Permission to the top level folder and several other folders, including custom folders Add an additional Exchange account by using your own credentials.
Full Access permission to a mailbox Add an additional Exchange account by using your own credentials.
As an alternative to these three methods, you can add another Exchange account by using additional mailboxes credentials. This method is not recognized as adding a shared mailbox, because you are adding the additional account by using its own credentials. To open the additional Exchange account, follow these steps:
  1. On the Tools menu, click Accounts.
  2. Click the Plus Sign to add an additional Exchange account.
  3. Enter the shared mailbox in the E-mail address field, and enter the shared mailboxes credentials under Authentication.