If your touchpad stopped working immediately after a Windows Update, the new driver might be buggy.
Sometimes the hardware simply glitches.
Often, the touchpad driver is still present but hidden. Here’s how to unhide it for free: hidcompliant touch pad free
The majority of users fix this simply by uninstalling the “Free” driver and rebooting (Method 2). Once the correct or Elan driver takes over, the word “Free” will disappear, and your touchpad gestures will return. If your touchpad stopped working immediately after a