How to restrict access to the registry from a remote computer (153183)

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By default on a Windows NT 3.51 system any user can access the registry when connecting over the network. On a Windows NT 4.0 system and later, by default only members of the Administrators group can access the registry over the Network.

Domain users can connect to the registry of a domain controller remotely by using Regedit.exe. They can then see values in the HKEY_CLASSES_ROOT entry and in the HKEY_USERS entry. However, they will have only read-only access. This is by design.

Note Some services need access to the registry to function correctly. For example, if you add this key to a 3.51 system that is running Directory Replication, it is necessary to grant the Replicator account access to the registry as described later in this article.

Restricting Network Access to the Registry

Warning 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.
Note In Windows 2000 and later, only Administrators and Backup Operators have default network access to the registry. This section may not apply in certain instances. To restrict network access to the registry, follow the steps listed below to create the following Registry key: The Security permissions set on this key define what Users or Groups can connect to the system for remote Registry access. The default Windows installation defines this key and sets the Access Control List to restrict remote registry access as follows: The default configuration for Windows permits only Administrators remote access to the Registry. Changes to this key to allow users remote registry access require a system reboot to take effect.

To create the registry key to restrict access to the registry:

1. Start Registry Editor (Regedt32.exe) and go to the following subkey:

   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control

2. On the Edit menu, click Add Key.
3. Enter the following values:

   Key Name: SecurePipeServers
   Class: REG_SZ

4. Go to the following subkey:

   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurePipeServers

5. On the Edit menu, click Add Key.
6. Enter the following values:

   Key Name: winreg
   Class: REG_SZ

7. Go to the following subkey:

   HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurePipeServers\winreg

8. On the Edit menu, click Add Value.
9. Enter the following values:

   Value Name: Description
   Data Type: REG_SZ
   String: Registry Server

10. Go to the following subkey.

    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurePipeServers\winreg

11. Select "winreg". Click Security and then click Permissions. Add users or groups to which you want to grant access.
12. Exit Registry Editor and restart Windows.
13. If you at a later stage want to change the list of users that can access the registry, repeat steps 10-12.

Bypassing the Access Restriction

Some services need remote access to the registry to function correctly. For example, the Directory Replicator service and the Spooler service when connecting to a printer over the network require access to the remote registry.

You can either add the account name that the service is running under to the access list of the "winreg" key, or you can configure Windows to bypass the access restriction to certain keys by listing them in the Machine or Users value under the AllowedPaths key.

   Value:        Machine
   Value Type:   REG_MULTI_SZ - Multi string
   Default Data: System\CurrentControlSet\Control\ProductOptions
                 System\CurrentControlSet\Control\Print\Printers
                 System\CurrentControlSet\Services\Eventlog
                 Software\Microsoft\Windows NT\CurrentVersion
                 System\CurrentControlSet\Services\Replicator

   Valid Range:  A valid path to a location in the registry.
   Description:  Allow machines access to listed locations in the
                 registry provided that no explicit access
                 restrictions exists for that location.

   Value:        Users
   Value Type:   REG_MULTI_SZ - Multi string
   Default Data: (None)
   Valid Range:  A valid path to a location in the registry.
   Description:  Allow Users access to listed locations in the
                 registry provided that no explicit access
                 restrictions exists for that location. 

Changed slightly in Windows 2000 and later:

   Value:        Machine
   Value Type:   REG_MULTI_SZ - Multi string
   Default Data: System\CurrentControlSet\Control\ProductOptions
                 System\CurrentControlSet\Control\Print\Printers
                 system\CurrentControlSet\control\Server Applications
                 System\CurrentControlSet\Services\Eventlog
                 Software\Microsoft\Windows NT\CurrentVersion
                 
   Value:  Users - Does not exist by default. 

For additional information about how to programmatically access the Windows registry and apply security to a registry key, click the following article number to view the article in the Microsoft Knowledge Base:

Note It is possible to have remote access to the registry after you follow the steps in this article if the RestrictNullSessAccess registry value has been created and is set to 0. This value allows remote access to the registry by using a null session. The value overrides other explicit restrictive settings.