1, the original file backup
sudo cp /etc/apt/sources.list /etc/apt/sources.list.bak
2, edit the source file list
sudo vim /etc/apt/sources.list
3, delete the original list, add the following
(DG Delete to end of the text
d1G to delete the text of the first)
Ali cloud sources
deb http://mirrors.aliyun.com/ubuntu/ great main
deb-src http://mirrors.aliyun.com/ubuntu/ great main
deb http://mirrors.aliyun.com/ubuntu/ great-updates main
deb-src http://mirrors.aliyun.com/ubuntu/ great-updates main
deb http://mirrors.aliyun.com/ubuntu/ great universe
deb-src http://mirrors.aliyun.com/ubuntu/ great universe
deb http://mirrors.aliyun.com/ubuntu/ great-updates universe
deb-src-updates http://mirrors.aliyun.com/ubuntu/ great universe
deb http://mirrors.aliyun.com/ubuntu/ great-security main
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-security main
deb http://mirrors.aliyun.com/ubuntu/ great-security universe
deb-src http://mirrors.aliyun.com/ubuntu/ xenial-security universe
4、更新源
更新软件包列表
sudo apt-get update
休复损坏的软件包，尝试卸载出错的包，重新安装正确版本的。
sudo apt-get -f install
升级系统中的所有软件包
sudo apt-get -y upgrade