Re: Left touchpad button doesn't work when the keyboard is in use.

Okay, I figured out why the button wasn't working. It wasn't a driver issue. It was because of the 8.1 update which reset the touchpad settings and has its own Palmcheck option. If updating software doesn't work for you, then this might be your problem.

1.  Move mouse right side of the screen to view pop up menu.
2. Click Settings.
3. Click Change PC Settings.
   
4. Click PC and Devices.
   
5. Click Mouse and Touchpad.
6. Underneath Touchpad, select No Delay from the drop down menu.

That should do it.