I have an application running on IIS 7.5 (Server 2008 R2). It uses Windows Authentication to grant users access to the website. Everything was working until suddenly today, users get an unauthorized error via IE (though it succeeds through Firefox). The problem disappears when I change the application pool to run as Network Service as opposed to ApplicationPoolIdentity. The only changes to the environment was the recent decommissioning of old 2003 domain controllers.
Anyone have any ideas what could cause this? (on a side note, is there a hidden IIS topic in the forums? I couldn’t find one)