My operating system windows vista home.

Suddenly touchpad not working please help for rectify.

Thanks.

Is your laptop a HP or Toshiba? [ if so ]
You can try and activate and deactivate the touchpad by using the function key [Fn] with the "F8" key.

If that doesn't work then...

Is the touch pad turned on?

Have you performed updates for vista/drivers?

Remove any programs?

Have you added any programs?

Did you have to re-install vista?