The lock button on my touch pad won't work

hi everyone,
I have an hp mini 210. I never knew how to lock my touch pad until recently. I found out in an online manual that I should be able to lock my touch pad using the button on the upper left corner of my touchpad.However, this button will click but seemingly does nothing. The opperating system I use is windows 7 starter. Any ideas on how I can get this button to work?
any help appriciated,
thanks,
Autumn