I got my Lenovo Ideapad Y500 a couple days ago. But when I had my mouse connected into the laptop and then turned off the touchpad, it would not turn back on. The only way I could get my touchpad to work again is by restarting the computer, which is pretty frustrating.
If you are experiencing erratic touchpad performance, have already updated to the latest driver from the Lenovo support site, have confirmed you have an Elan touchpad and verified that your system was built before December 2012, please contact service under warranty. Service will confirm problem determination and will schedule service as appropriate.