The little experience I have had with OWA (Outlook Web Access email) seems to be that it needs a web browser to access the OWA portal set up by the email admin. It's not a "regular" email client in the sense that you can access the mail directly.  You have to use the portal via a web browser.

This from Office online "help" - With Office Outlook Web Access, you can use a Web browser to access your Microsoft Exchange Server mailbox from any computer with an Internet connection.