We had a problem with Barracuda’s ADC load balancer and Outlook Web App for Exchange 2013. The user would get to the OWA login screen and login only to be brought back to the login screen again in an endless loop. We were using the “Instant SSL” service type as described in the following Barracuda document: https://techlib.barracuda.com/adc/msx2013deploy
The problem was that “Rewrite Support” was enabled on the service. Disabling this allowed the users to login without problem.