Step 1:
Open Outlook. Select Tools, then Accounts.

Step 2:
In Accounts, select your UTHSCSA account.

Step 3:
Select the Delegates & Sharing tab.

Step 4:
Navigate to the Shared With Me tab. Select the + to get started with adding the shared mailbox.

Step 5:
Now search for the mailbox name. Select Add. Ensure the correct mailbox is selected, then select Ok.

The mailbox is now added, and you will see in the left pane of your outlook.
