All of these people and no answer i think i figured it out go to your system preferences. You will need to have a working mouse to get there obviously. Once your there go to Accessibility then click on the mouse and trackpad option. Once you are there you will most likely have ignore built in trackpad while using mouse. Uncheck that and your track pad should work now. You can disconnect your mouse and you should be good to go. At least thats what worked for me hope that helps.