Managing personal Outlook.com account settings, security, and privacy
I had similar issue faced with my iphone6 mail app, displaying "Cannot Get Mail". After a couple of troubleshooting, the final solution to this error message was due to "Two Way Verification" from your personnel Password and Security Settings. Hence, log in to your own account and switch off the two way verifcation to allow the smartphone mail app to retrieve mails directly through a single password.
Hope this helps everyone out there. Nothing wrong with IOS8.3....