Users who are running inside a Citrix session are unable to access my ASP.NET 3.5 sites.  However, they can access SQL Reporting Services Report Manager and a different server's SharePoint installation and both of those identify them by their domain name properly.

I'm assuming I'm screwing something up in the way I setup security for my ASP.NET apps OR something I did incorrectly in IIS?

Does Citrix handle authentication differently in some way that I need to account for?

 

The users see this error:

You are not authorized to view this page

You do not have permission to view this directory or page using the credentials that you supplied because your Web browser is sending a WWW-Authenticate header field that the Web server is not configured to accept. Go to the complete details ...