(1) 输入sudo service network-manager stop
(2) sudo rm /var/lib/NetworkManager/NetworkManager.state
(3) sudo service network-manager start
(4) sudo vim /etc/NetWorkManager/NetworkManager.conf，将其中的managed=false改为managed=true 或者使用gedit，采用图形化界面的方式更改
(5) sudo service network-manager restart
sudo service network-manager stop
sudo rm /var/lib/NetworkManager/NetworkManager.state
sudo service network-manager start