How to fix if the touchpad sensor that controls the volume does not work?

Touch Sensor that controls the volume, AV Mode, play, fast forward and rewind has stopped working.

Reinstall the Synaptics Pointing Driver (Touchpad) when this symptom occurs.
1. Click Start
2. Click My Computer
3. Double-click Local Disk  C:
4. Double-click Windows folder
5. Double-click Drivers folder
6. Double-click Pointing Driver (Synaptics)
7a. Double-click on Setup to install the file (C:\Windows\Drivers\Pointing Driver\Setup.exe
   OR
7b. Reinstalling the Synaptics driver from www.sony-asia.com download section will also resolve the issue

Note:  Reinstalling the Pointing Driver (Synaptics) from VAIO Recovery will not resolve this issue.