title: IIS 401.1 error
body: <p>We have a .net web application running on iis 8 using windows authentication.
  Everything was working fine until we installed a new version of our application without any changes to the iis settings or in the apps web.config file. 
  The problem is that ever since when we try to open up the app in a browser and fill out the windows authentication popup with valid user user information, it just wont authenticate and after the third try we get a 401.1 error message. This happens when we try to access the website from any pc even the pc that hosts iis and even when we try to launch the site through iis.
  Any ideas on what could cause such a thing?</p>