Sorry for another question about ubuntu hanging on shutdown and reboot. I have looked at other questions on the site and tried editing the grub file etc as per most answers but to no avail. I have not tried reinstalling ubuntu-desktop or unity as per some answers as I'm unsure what the effect will be.
I have been running ubuntu 14.04 on my laptop, a clevo, for over a year now with no issues. Ubuntu is the only operating system on the computer. Last night it started to hang on shutdown and reboot. Have tried shutting down through os and terminal and neither work. Last thing I was doing before this problem occurred was trying to add a Canon LBP printer as per this ubuntu guide. Dont't know if that could be related or not.
Ideally I would like to know how to find out what is preventing the shutdown and how to fix it.
Below is a screen shot of what happens when I try to shut down. I am able to shut down at this point by pressing the power button on the laptop. If you need any more details let me know.