Note: This guide has been created using Outlook 2013.
1. Open outlook and click the file menu in the top left corner as indicated below by the red arrow.
2. At the Account Information screen, please click Add Account.
3. Fill out the form with the account details. The contents of the Your Name field will be the account name the recipients of your emails will see. Once you have filled it out please click the Next button in the bottom right corner.
4. Outlook will go through its automatic configuring process. Provided the details are correct it will complete and you will be able to finish adding the account in. Please click the Finish button once it has finished configuring.
5. You may be presented with another authentication screen. If yes, enter your second mailbox address and password. Click Sign In
If not, press OK and restart Outlook.
6. When Outlook restarts, the second mailbox will appear underneath your other mailbox. Note that you may have to scroll down to find it.