I have just recently upgraded from 14.04 to 14.10 Ubuntu. I had this problem too, for an entire week now. couldn't edit users, network, suspend, shutdown, etc. tried every single solution to no avail. In the end i've repeated apt-get update/apt-get upgrade and it's fixed. Also fixed the pulseaudio sound problem i had and never figured out a solution for it. Linux desktop is a nice project, unfortunately riddled with bugs, and missing direction.
I have just recently upgraded from 14.04 to 14.10 Ubuntu. I had this problem too, for an entire week now. couldn't edit users, network, suspend, shutdown, etc. tried every single solution to no avail. In the end i've repeated apt-get update/apt-get upgrade and it's fixed. Also fixed the pulseaudio sound problem i had and never figured out a solution for it. Linux desktop is a nice project, unfortunately riddled with bugs, and missing direction.