TL;DR
You have to enable xenial-updates and xenial-security in your /etc/apt/sources.list
or on Updates tab of Software & Updates (software-properties-gtk
).
It seems that you incorrectly understand the pool folder structure. It contains all packages for all releases.
You should go to https://packages.ubuntu.com and run search for chromium-browser package amd64 to determine correct versions for your current release.
Then you will get the following for xenial and xenial-updates:
xenial (16.04LTS) (web): Chromium web browser, open-source version of Chrome [universe]
78.0.3904.108-0ubuntu0.16.04.1 [security]: amd64
xenial-updates (web): Chromium web browser, open-source version of Chrome [universe]
78.0.3904.108-0ubuntu0.16.04.1: amd64
So you can get the latest possible package version from universe pocket:
78.0.3904.108-0ubuntu0.16.04.1: amd64
On my fully updated system the output is the following:
$ apt-cache policy chromium-browser
chromium-browser:
Installed: 78.0.3904.108-0ubuntu0.16.04.1
Candidate: 78.0.3904.108-0ubuntu0.16.04.1
Version table:
*** 78.0.3904.108-0ubuntu0.16.04.1 500
500 http://archive.ubuntu.com/ubuntu xenial-updates/universe amd64 Packages
500 http://archive.ubuntu.com/ubuntu xenial-security/universe amd64 Packages
100 /var/lib/dpkg/status
49.0.2623.108-0ubuntu1.1233 500
500 http://archive.ubuntu.com/ubuntu xenial/universe amd64 Packages
In your particular case it seems that xenial-updates is missed in your /etc/apt/sources.list
file. You need to re-enable it from terminal or by visiting Updates tab of Software & Updates (software-properties-gtk
) .
Also I need to note that current Ubuntu 16.04 LTS version is 16.04.6 LTS.
So really you need to enable xenial-updates, xenial-security, then update package lists with sudo apt-get update
and install all newest dependencies with sudo apt-get dist-upgrade
. This will solve many security- and update- related problems.
Best Answer
I would say a few things.
First, I need to caution you against using the command
su
-- it is a bad practice that can only cause problems. When you need administrative privileges, you should prefix your normal commands withsudo
. If you really need a root prompt, you can usesudo -i
.Now I took a look at the x2go wiki page and they didn't intend for you to blindly add that line to the bottom of /etc/apt/sources.list. If you're not too familiar with how Ubuntu handles packaging, you should spend some time on it. Luckily, you don't really need to be doing any of this from the command line because Ubuntu provides a graphical way to ensure that you don't drop syntax errors in your sources.list or elsewhere.
In order to use the built-in tools for enabling or disabling certain repositories, try this link. This will save you from syntax errors and from messing with system-critical files inadvertently.
Secondly, as soon as you modify any of your ubuntu repositories, you should run:
As this will refresh your package information. After you run that, you should run
This will clean up your repository caches. Now try adding the PPA again, this time using sudo:
If it still doesn't work, you'll need to re-run the command using the -m flag and show us the output:
Hope this helps!