Event ID - 1000

Event Id1000
SourceUserenv
DescriptionDescription :
1.
The Group Policy client-side extension Security has passed flags (17) and returned a failure status code of (3). >
2.
Windows cannot unload your registry class file. If you have a roaming profile, your settings are not replicated. Contact your administrator.
DETAIL Access is denied. , Build number ((2195)).
3.
Windows cannot determine the user or computer name. Return value (1722).
4.
Windows cannot access the registry information at \\Domain_Name.com\sysvol\Domain_Name.com\Policies\{31B2F340-016D-11D2-945F-00C04FB984F9}\Machine\registry.pol with <Error code>.
5.
Windows cannot establish a connection to <domain> with <Error code>.
5.Windows cannot read the history of GPOs from the registry.
Event InformationAcconding to Microsoft:
CAUSE 1:
This issue may occur if the computer account for the computer listed is corrupted.
causes 2: 
Missing/incorrect Policies directory structure will create this issue.Replication service will try to replicate but cannot locate it

RESOLUTION:
To resolve this issue, join the computer to a workgroup named WORKGROUP, and then restart the computer. Rejoin the computer to the domain, and then restart the computer again.
CAUSE 3.:
This behavior occurs if the SMB signing settings for the Workstation service and for the Server service contradict each other. When you configure the domain controller in this way, the Workstation service on the domain controller cannot connect to the domain controllers Sysvol share. Therefore, you cannot start Group Policy snap-ins. Also, if SMB signing policies are set by the default domain controller security policy, the problem affects all the domain controllers on the network. Therefore, Group Policy replication in the Active Directory directory service will fail, and you will not be able to edit Group Policy to undo these settings.
RESOLUTION:
If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.

CAUSE 4.:
These problems may occur when the following conditions are true:
1.You install the original release version of Microsoft Windows 2000 on a Microsoft Windows NT 4.0 domain controller.
2.A DNS suffix is defined in the Network control panel item of the domain controller.
When you install Windows 2000, the Windows 2000 Setup program automatically unchecks the Change primary DNS suffix when domain membership changes check box. Setup also sets the primary DNS suffix to the first suffix that is list
Reference LinksLinks related to Description 1:

Trobleshooting Group Policy In Windows Server

Event ID 102 and Event ID 1000 are logged in Event Viewer when you log on to your Microsoft Windows 2000-based computer or your Microsoft Windows Server 2003-based computer

Error Messages After Importing Basicdc.inf into Group Policy

Event ID 1000 and 1001 Repeat Every 5 Minutes in the Event Log

Event ID 1000 is logged on Windows 2000 domain controllers

Cannot Access Group Policy Objects--Event ID 1000 and Event ID 1001 Logged

SceCli Event ID 1001 and UserEnv Event ID 1000 When Dfs Client Is Disabled

Event ID 1000 and 1202 After Configuring Policies

ESENT event IDs 1000, 1202, 412, and 454 are logged repeatedly in the Application log

Packages Assigned to Computers with Group Policy Are Not Installed

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