After save config in NetworkManager, I put in terminal command: "ifconfig". The changes saved from NetworkManager does not applying, and configuration interface is empty.
I try for DHCP AND manual (static) configuration.
I configured connection manually by ifconfig command, but NetworkManager overwrite by empty configuration NetworkManager.
I copied NetworkManager configuration from working copy ubuntu 10.04 to ubuntu 12.04.01 and still don't save configuration, on connection eth0.
Ubuntu 12.04.01 Installed from USB, In previously Ubuntu version 10.04 work fine.