1. Log into Outlook Web App at http://na01.msexchangeoutlook.com.
2. Click on the name of your account in top right corner.
3. Type the email address of the mailbox that you have permission to access.
4. Click Open.
Opening another User's Mailbox in Outlook Web App 2010
Modified on: Thu, 25 May, 2017 at 1:18 PM