Hi, we have a custom OWIN config to authenticate CMS users via Active Directory and "Windows Authentication" in the web.config for front-end users (this is for an Intranet).

It works fine when Umbraco is not running over SSL but as soon as you enable SSL then the preview mode fails (white screen with loading icon) and eventually (if you don't close it quick) it kills the app pool.

Similarly, if you leave SSL enabled but disable Windows Authentication (changing it to Forms authentication) then preview works fine. It just won't work with SSL and AD Windows Authentication.

Any ideas? I've done a lot of research and come up with lots of preview issues and AD scenarios but can't find anything to solve this.