How do I fix my unresponsive touchpad?

How do I fix my unresponsive touchpad? 

4. Enable the touchpad
  1. Press the Windows key and type “Touchpad”. Then select Touchpad settings.
  2. Check to see if the touchpad is activated. If it’s turned Off, press Shift + Tab to navigate through the options.
  3. Press the Spacebar to turn the touchpad feature On, then test the touchpad to see if it works.