title: How to integrate SiteMinder SSO Authentication and Windows Authentication for .NET 4.0?
body: <p>My problem is this, we have a set of legacy code that runs SiteMinder but very poorly.  It allows Anonymous at IIS and avoids any use of Active Directory.  </p>
  
  <p>We are rebuilding this application and would like to integrate SiteMinder with IIS and .NET 4.0.  I know that I can come in and build my own security framework that does everything without the need of a User Name and Password (because we don't want that from SiteMinder), but I was wondering if there is a way to use the built in Windows Authentication (Forms or Windows) to integrate with SiteMinder.  </p>
  
  <p>Additionally I saw that older versions of .NET had Passport Authentication, but it has been removed.  I think this might actually solve our problem but it isn't supported in the most recent versions of .NET (I.E. beyond 1.1).  </p>
  
  <p>Any and all information regarding SiteMinder integration with ASP.NET 4.0 would be more than welcome.  I've tried to stitch together enough information to get it working.  </p>
  
  <p>I know that SiteMinder returns a set of customizable headers.  I want to use the fact that we have a verified Header that contains a Unique Identifier to log a user in, while at the same time using Windows Authentication.  Any guidance would be appreciated.  I'd really like it if we could create a guide to integrating SiteMinder and ASP.NET (because I haven't found one) but if anyone knows of something like that please post it up!</p>