|"FN/F9 does not disable the mouse pad "|
Are you SURE that's the right key combo ?
Did you hold down Fn, then press the other key, then let go of both ?
Did you look in the Owner's or User's manual ?
On an Acer laptop I have it's Fn and F7.
The F7 key has a second blue icon that looks like the outline of a touchpad with a solid hand with an out stretched finger above it.