All MPexchange / Business365 2FA authentication issues for login to OWA have now been resolved. We apologise for any inconvenience.
Posted Nov 19, 2019 - 09:05 AEDT
The upstream provider has informed us that the login page for OWA(webmail) is having issues when coupled with 2 factor authentication, causing a 504 Gateway timeout error. The root cause has been identified and we expect a fix to be applied soon.