Synaptic touchpad on laptop not working

I'm using a laptop with built-in touch-pad that works in Windows 7. But after I switched to Ubuntu 12.04 LTS, it's not working now.

Solution 1:

This seems to be a bug in 12.04.2. As stated in comments, a simple fix would be unloading the mouse driver and load it again like this:

sudo modprobe -r psmouse
sudo modprobe psmouse proto=imps

This only keeps the touchpad working on this session. To make it permanent one can create a file like /etc/modprobe.d/psmouse.conf (you can choose the name you want, but you must keep the extension) with the following content:

options psmouse proto=imps