This hack prevents standard Registry tools: Regedt32, Regedit, and Tweak UI from running. This restriction will only protect against the casual, unsophisticated user. After this registry hack, when one attempts to run the Registry editors, they exit with a brief security messsage.

Hive: HKEY_CURRENT_USER
Key: Software\Microsoft\Windows\CurrentVersion\Policies\System
Name: DisableRegistryTools
Type: REG_DWORD
Value: 1

To prevent remote editing of registry. This setting can be controlled by the policy editor. This item is found in the Common.adm template, User\System, Disable Registry Editing Tools checkbox.