Outlook Web App is used to access e-mail (including support for S/MIME), calendars, contacts, tasks, and other mailbox content when access to the Microsoft Outlook desktop application is unavailable.
To access your account via OWA:
Navigate to http://exchange.emailservice.io/ in your web browser.
Enter your full email address and password
You will then be logged in to a web portal that is very similar to what you would see in your Outlook client