Enable Ctrl+Alt+Delete in Windows Vista
Windows Vista don't have Ctrl+Alt+Delete support by default, but no worries we can enable this feature easily.
Follow the below steps:
(*) Start -> Run -> type netplwiz.
(*) In the Pop up window go to Advance -> Select Require user to press ALT+CTRL+DEL.
(*) Click Ok.
(*) Reboot the system.
Now Ctrl+Alt+Delete option enabled.