I have 14.04, installed with 3G main disk, 8GB memory. I initially tried to set it up as a DHCP server, but gave some bad configuration data and it lost eth0 connection. Upon reboot, the NetworkManager icon in the system try does not exist. If I attempt to go to "System Settings" and select the Network icon. I receive an error message that it's a version problem. I've taken a couple of screen shots so you can see the displayed results of items.
I've removed and re-installed the NetworkManager. When I execute the 'nmcli con' one of the lines mentioned is
Ethernet 0 5620e493-5125-48e3-a3c4-6e35fe351a07 802-3-ethernet Wed 11 Nov 2015 08:58:15 PM MST
This timestamp is at least 5 days old, and is my main connection out of this box. I'm starting to wonder if it's really working or something else is running instead. Since I'm on here with it, this is working and no other connections are valid. Any suggestions would be appreciated.