When trying to access outlook web access on SBS 2011 by going to https://yourserver/owa. You see the login prompt but after entering your credentials, you are faced with a blank page with https://yourserver/owa/auth.owa in the address bar.
This is normally due to the Forms based authentication service not running. Sometimes it fails to start when a PC restarts.
To resolve the issue:
- Open Services
- Start the Microsoft Exchange Forms-Based Authentication Service
Job Done!