Under t hat menu, find Remove and prevent access to Shut Down command, double click on that to open a setting dialog box.

• Set it to enabled to disable the turn off option on your windows.
• Set it to disabled to enable the turn off option on your windows.

Setting for Log off option:

Follow the same procedure as above, but choose Remove Logoff on start menu in step 4.

Here is the explanation for Remove and prevent access to shut down command as provided by Microsoft:

Prevents users from shutting down or restarting Windows.

This setting removes the Shut Down option from the Start menu and disables the Shut Down button on the Windows Security dialog box, which appears when you press CTRL+ALT+DEL.

This setting prevents users from using the Windows user interface to shut down the system, although it does not prevent them from running programs that shut down Windows.

If you disable this setting or do not configure it, the Shut Down menu option appears, and the Shut Down button is enabled.

Note: It is a requirement for third-party applications with Windows 2000 or later certification to adhere to this setting.

And the below one for Remove logoff from start menu:

Removes the "Log Off " item from the Start menu and prevents users from restoring it.

If you enable this setting, the Log Off item does not appear in the Start menu. This setting also removes the Display Logoff item from Start Menu Options. As a result, users cannot restore the Log Off item to the Start Menu.

If you disable this setting or do not configure it, users can use the Display Logoff item to add and remove the Log Off item.

This setting affects the Start menu only. It does not affect the Log Off item on the Windows Security dialog box that appears when you press Ctrl+Alt+Del, and it does not prevent users from using other methods to log off.

Tip: To add or remove the Log Off item on a computer, click Start, click Settings, click Taskbar and Start Menu, click the Start Menu Options tab and, in the Start Menu Settings box, click Display Logoff.

See also: "Remove Logoff" in User Configuration\Administrative Templates\System\Logon/Logoff.

Thanks Pavan Kumar]