This event was caught by the catch-all rule for UserEnv events. This Management Pack may have been released before this event was defined.
The most likely cause is that the domain controller has been upgraded with a service pack, hotfix, or operating system upgrade, and the Active Directory Management Pack has not been upgraded.
To upgrade to the latest version of the Active Directory Management Pack, see the Management Pack Catalog at http://go.microsoft.com/fwlink/?LinkId=82131.
To enable UserEnv logging, see Knowledge Base article 221833, “How to Enable User Environment Debug Logging in Retail Builds of Windows,” at http://go.microsoft.com/fwlink/?LinkId=25636. The log file provides details for the specific error.
Microsoft Help and Support for Microsoft Windows Server 2003
Microsoft Knowledge Base