This documentation is archived and is not being maintained.

WindowsImpersonationContext.Undo Method

Reverts the user context to the Windows user represented by this object.

Namespace:  System.Security.Principal
Assembly:  mscorlib (in mscorlib.dll)

public void Undo()


An attempt is made to use this method for any purpose other than to revert identity to self.

Notes to Implementers

Because Microsoft Windows 98 and Windows Millennium Edition platforms do not have users or user tokens, impersonation cannot take place on those platforms.

The following example shows how to impersonate a Windows identity using a specified user token.

WindowsImpersonationContext ImpersonationCtx = WindowsIdentity.Impersonate(userToken); 
//Do something under the context of the impersonated user.

.NET Framework

Supported in: 4, 3.5, 3.0, 2.0, 1.1, 1.0

.NET Framework Client Profile

Supported in: 4, 3.5 SP1

Windows 7, Windows Vista SP1 or later, Windows XP SP3, Windows XP SP2 x64 Edition, Windows Server 2008 (Server Core not supported), Windows Server 2008 R2 (Server Core supported with SP1 or later), Windows Server 2003 SP2

The .NET Framework does not support all versions of every platform. For a list of the supported versions, see .NET Framework System Requirements.