Hi @Palmer, David,
You can view the sent items that he authorized when add another person’s mailbox to your profile .
You could refer to the following steps to add another mailbox to profile:
1. Click file- info- Account Settings- Account Settings
2. In the E-mail tab, make sure your account is selected, then click on Change.
3. Click the More Settings button.
4. Click on the Advanced tab and then click on Add.
5. Enter the email address of the delegated mailbox in the Add mailbox field. Then click on OK.
6. After save this setting, close the Account Settings window. You should now see both mailboxes in your Outlook profile.
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