Resetting user display settings in 12.10

view story

http://askubuntu.com – I have a macbook air with intel graphics, yesterday I disabled the laptop screen while I used an external screen and today whenever I plug it in the laptop screen goes off and the external monitor does not come on. I am pretty sure the setting is stored under my user as the login screen appears on both screens if I plug in the external at the login screen or if I start with it plugged in but vanishes as I log in. Thanks, Tom (HowTos)