Comment 3 for bug 1485274

Ubuntu forum post fixed problem on Lenovo. Will try Acer next:

http://ubuntuforums.org/showthread.php?t=2290845&p=13339649#post13339649

Xubuntu failed using autologin.
The fix is to remove the line "autologin-session=lightdm-autologin" from "/etc/lightdm/lightdm.conf, as that option has been unimplemented, per post#8 from this
bug report. #1484083

I'm using Ubuntu Unity fix worked for me as well.