Package software-properties-common is not available, but is referred to by another package.
This may mean that the package is missing, has been obsoleted, or
is only available from another source
E: Package 'software-properties-common' has no installation candidate
System: Ubuntu 16.04
This package exists in xenial repositories, so make sure your /etc/apt/sources.list file contains the next entries uncommented:
deb http://us.archive.ubuntu.com/ubuntu/ xenial main restricted
deb http://us.archive.ubuntu.com/ubuntu/ xenial-updates main restricted
deb http://us.archive.ubuntu.com/ubuntu/ xenial universe
deb http://us.archive.ubuntu.com/ubuntu/ xenial-updates universe
deb http://us.archive.ubuntu.com/ubuntu/ xenial multiverse
deb http://us.archive.ubuntu.com/ubuntu/ xenial-updates multiverse
deb http://us.archive.ubuntu.com/ubuntu/ xenial-backports main restricted universe multiverse
deb http://security.ubuntu.com/ubuntu xenial-security main restricted
deb http://security.ubuntu.com/ubuntu xenial-security universe
deb http://security.ubuntu.com/ubuntu xenial-security multiverse
Then do sudo apt update and try again
sudo apt-get update– user535733 Mar 22 '20 at 15:24