1.  停止 network-manager服务

sudo service network-manager stop

2. 备份一下文件

sudo cp /var/lib/NetworkManager/NetworkManager.state  /var/lib/NetworkManager/NetworkManager.state.back

3.删除文件

sudo rm /var/lib/NetworkManager/NetworkManager.state

4.重启服务

sudo service network-manager start

5.重启系统

reboot

6.修改网卡图标在桌面又上角显示

sudo gedit /etc/NetworkManager/NetworkManager.conf

7.把对应的选项修改一下：

managed = true