A hotfix is available that enables Microsoft ASP.NET Web applications to support claims-based identities when you use membership providers to authenticate users in your application. To achieve that, the FormsIdentity class and the RolePrincipal class are now unsealed in the .NET Framework Class Library.
Hotfix Replacement Information
The hotfix that corresponds to KB971993 has been superseded with the hotfix KB981201, which contains all fixes that were previously included in KB971993. You should use the hotfix KB981201 to fix the issues described in KB971993. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
981201 A hotfix is available for ASP.NET 2.0 that enables support for extended protection
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
For more information about claims-based identity, visit the following Microsoft Web site: