How to disable automatic disk defragment in windows vista?

How to disable automatic disk defragment in windows vista?

Windows Vista uses an always-on defragment set up that isn’t that
necessary and will cause your system to slow down. Remember to
run a defragment manually once a month.
To shut down this feature follow this simple steps:-
.....
1. Click the Start button
2. Select Computer
3. Right-click on C: Drive icon
4. Select Properties
5. Click the Tools tab
6. Uncheck Run on a schedule
7. Click OK
.