This policy setting disables or removes all menu items and buttons that log the user off the system.If you enable this policy setting users will not see the Log off menu item when they press Ctrl+Alt+Del. This will prevent them from logging off unless they restart or shutdown the computer or clicking Log off from the Start menu.Also see the 'Remove Logoff on the Start Menu' policy setting.If you disable or do not configure this policy setting users can see and select the Log off menu item when they press Ctrl+Alt+Del.
Policy path:
System\Ctrl+Alt+Del Options
Scope:
User
Supported on:
At least Windows 2000
Registry settings:
HKCU\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer!NoLogoff
Filename:
CtrlAltDel.admx