Update causes blank screen/can't log in

[aleddilwynfisher]

Hi,

I got a message asking to update Ubuntu and started the update.

Things were going fine but suddenly I got a blank screen and, after a long wait and the laptop going quiet besides the fan, I had to switch it off.

I switched it back on and just get the console, which I have little/no experience of. I tried sudo apt-get update as suggested elsewhere but it doesn't seem to work (just says it couldn't download most things). Also tried other suggestions elsewhere, like sudo init 3 and sudo init 5. Just says 'PolicyKit daemon disconnected from the bus. We are no longer a registered authentication agent.'

What can I do? I am very new to Ubuntu and the laptop came with it preinstalled. Very worried about losing work on there.

Thanks,
Aled

[pickarooney]

does typing startx when you have logged in to the console do anything?

[aleddilwynfisher]

Just tried that - seemed like things were happening as the console disappeared for a bit, but now I'm back there. Lots of code... Last thing it says is "waiting for X server to shut dow. (II) Server terminated successfully (O). Closing log file"

[aleddilwynfisher]

I should've said - when I turn it on, I get the Dell logo as normal, then the Ubuntu logo as normal, but before the usual log-in screen, it goes into text with my computer name and 'tty1', and asks for my login and password. After typing them in, I can do commands.

[Bashing-om]

aleddilwynfisher; Hello;

As you can log in via the terminal, the situation is salvageable .

We need to know what release and what (D)esktop (E)nvironment you are running. ( unity, gnome kde, xfce ??)
Then we can examine what is not taking place in the GUI .



it ain't nothing but a thing

[aleddilwynfisher]

Thanks for helping!

Not sure what any of that means to be honest (I bought a new laptop with Ubuntu Linux 14.04 pre-installed) but, after a quick Googling, it looks most like Unity.

Is there any way I can find out for sure? And, if it is Unity, what should I do?

[Bashing-om]

aleddilwynfisher; Hey ...

The situation could arise from a number of different causes.
We begin the process of discovery:
To know what the DE is ( I bet as pre-installed ubuntu it is in fact 'unity'):
Post back the outputs - Between code tags - of terminal commands:


lsb_release -a
uname -a
echo $DESKTOP_SESSION " " $XDG_CURRENT_DESKTOP

These tell us what release you are running, the booting kernel info, and the Desktop employed in this install.

Next we want to insure that the package manager is in a consistent state:


sudo apt update
sudo apt full-upgrade
sudo apt -f install
sudo dpkg -C


And as a 1st approximation of where the problem may lie we will want to know what is taking place in the X layer :


cat /var/log/Xorg.0.log


All this ->



just clearing the deck for action