What happens to the monitor, how to connect?

Question

linux

Kind. Tell me, in general, I turned off the external monitor on the laptop, correctly (through the settings, with a button), after a reboot, it seems to load, everything is duplicated from the laptop screen to the monitor, after logging in under my account, the monitor goes out, then it can no longer be turned on on the laptop (in the same settings, the button turns on and immediately turns off, nothing happens). If you enter under the guest account, then the monitor immediately works, and everything is fine.
OS Elementory
3.16.0-34-generic #45~14.04.1-Ubuntu SMP Tue Mar 24 11:13:52 UTC 2015 i686 i686 i686 GNU/Linux

Answer 1

You can enable it via xrandr.
xrandr --output LVDS1 --auto

Answer 2

I'm guessing it's the drivers. If the video card is nvidia, then you need to look towards xorg.conf

Answer 3

turn on the monitor in your account through the settings - screen resolutions - find - further as usual.
you disabled it in your account, and left that's all in the guest account.