Sending, receiving, and organizing email in Outlook.com
What is the part of your address after the @ sign?
If its an outlook.com, hotmail, live, or msn address - everything in new Outlook will be in Outlook on the web.
If you are not using an outlook.com account in new Outlook, you won't have the mail available in outlook.com on the web. That is only for outlook.com email addresses.
Let me know how it goes, I'm here to help you further if needed.
-- Diane