Option 1: Updating the Exchange CAS servers As for Internet Explorer 11, due to a change in the User Agent String of the browser on Windows 7 and Windows 8, the Exchange Server does not recognize the browser as a supported version and the user instead receives the simpler OWA Light interface.įor scenarios where OWA Premium is not supported for a given Exchange/Browser combination, OWA Light may be served to the user and breaks in functionality may occur. Without the latest updates installed for Exchange 2010 and Exchange 2013, only IE10 and lower are fully supported with OWA Premium. What Causes this to Happen?Įxchange determines which version of OWA (OWA Premium or OWA Light) to use based on the user agent string that the web browser supplies to the server during communications (for more information on user agent strings, see the references below). If your IT Department has not installed the latest updates for Exchange 2010 and you log in to your email using IE11, you will see the OWA Light user interface instead of the OWA Premium user interface that you are used to seeing and using.

If you are an early adopter of Windows 8.1 or Internet Explorer 11, you may notice some functionality and compatibility issues present when you access your corporate mail via Outlook Web App.