Hi, I've developped an application using asp.net which uses users' authentication through Active Directory. When I deploy the application on a server using Windows 2000 (Sp3) with Active Directory , it works, but after installing SP4, I get the message below (in the authenticating page using identity impersonation):


Server Error in '/Jlec' Application.
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Accès refusé (= Access Denied).
Description: An unhandled exception occurred during the execution of the current web request. Please review the stack trace for more information about the error and where it originated in the code.

Exception Details: System.ApplicationException: Accès refusé.

Source Error:

An unhandled exception was generated during the execution of the current web request. Information regarding the origin and location of the exception can be identified using the exception stack trace below.

Stack Trace:


[ApplicationException: Accès refusé(= Access Denied).
]
System.Security.Principal.WindowsIdentity._ResolveIdentity(IntPtr userToken) +0
System.Security.Principal.WindowsIdentity.get_Name() +71
System.Web.Configuration.AuthorizationConfigRule.IsUserAllowed(IPrincipal user, String verb) +100
System.Web.Configuration.AuthorizationConfig.IsUserAllowed(IPrincipal user, String verb) +81
System.Web.Security.UrlAuthorizationModule.OnEnter(Object source, EventArgs eventArgs) +178
System.Web.SyncEventExecutionStep.System.Web.HttpApplication+IExecutionStep.Execute() +60
System.Web.HttpApplication.ExecuteStep(IExecutionStep step, Boolean& completedSynchronously) +87




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Version Information: Microsoft .NET Framework Version:1.1.4322.573; ASP.NET Version:1.1.4322.573

Thanks in advance