Script to Lock windows workstation (Like Win + L)

To simulate Win + L action to lock your windows workstation, we can use User32.dll API. The reason why we use API is because virtual keys doesn't work here to simulate win + L OR Ctrl+Alt+Del to lock your workstation.
Example:
cmd>Rundll32.exe user32.dll,LockWorkStation

Reference:
http://www.autoitscript.com/forum/topic/21848-functions-in-user32dll/