Ubuntu系统的网络服务与此版本的网络管理器不兼容问题解决方法

After that go the correct folder.
# cd /etc/NetworkManager/system-connections/
Now take a look at the content of this folder. If you had a VPN connection e.g. there must be a file with the name of that connection.

# ls -la
Now you can remove that file or you can move it to another folder (so you can set it back if this solution does not work for your problem).

To move the file to your personal folder use the following command:
# mv <filename> /home/<username>/ #username是你的用户名

Now the only thing left is starting the Network Manager:
# NetworkManager

当～～～你的网络管理界面里出现了久违的无线网卡～LOL

PS：可能会出现未配置的情况，请reboot一下