Office 365 compatibility is typically best with the current or the immediately previous version of Internet Explorer or Firefox, and the latest version of Chrome or Safari. To check to see if your browser is up-to-date, go to https://updatemybrowser.org/. If you are opening Outlook on an outdated browser, it will switch to "Outlook Light" which has limited features. After you update your browser, you may need to turn off the "Outlook Light" settings. Please see Office 365 (Web) - Change Outlook Light to Outlook Web App .
Office 365 on the Web is not dependent on your operating system. Please click on the links below for more information: