How to lock your system with your PD

Hey guys its a new trick to lock your system with your PD 
(this trick is work on any windows system)
start follow this steps:

1.Change your PD letter or volume to A:
 type in run diskmgmt.msc

now from here you can convert your PD to A:
just insert your PD select it and by Right click on it you get an option to 
change the drive letter path and change it by assigning drive letter to A

now you only have to do this.
just type syskey command in your run dialog

now click on update command
 

now select store start up key on floppy disk
.
now enjoy the lock bt remember  
you can unlock ur system only when you insert
your PD