scroll bar on HP Pavillion
 

Help - I sometimes tap the touchpad in the wrong way and end up disabling the scroll bar. I can't seem to find out where exactly I should be tapping to turn it on and off.
Although it's not the end of the world because I can move the cursor to the right of the page and scroll that way it's VERY annoying.

Hopefully somebody will tell me where exactly to tap the touchpad.