Certain tools in Vista can be used to maliciously or innocently wreak havoc on a computer. Although such tools are useful in specific situations, you may want to disable access to some of these tools to prevent unwanted changes to your computer.

Task Manager is one such tool that can produce negative results, such as system instability, when used incorrectly. You can prevent users from accessing Task Manager by disabling it through the Registry Editor.

To disable Task Manager in Vista using the Registry Editor:

1. Open the Registry Editor.
2. Navigate to:
   HKEY_CURRENT_USER \ Software \ Microsoft \ Windows \ CurrentVersion \ Policies \ system.
3. Create a new DWORD value named DisableTaskMgr.
4. Set the value to 1 to disable Task Manager.

The steps above will disable Task Manager for the current user. To undo these steps, simply change the value in step 4 to ‘1′.