I downloaded the Upwork desktop App on ubuntu 18.04. When I open it with Gdebi package installer I saw this error:

enter image description here

I tried to install gksu manually via sudo apt install gksu but I got this error

Building dependency tree       
Reading state information... Done
Package gksu 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 'gksu' has no installation candidate

How can I install this software on ubuntu 18.04 (I download it yesturday so it is the most recent version on upwork website) ?

  • 1
    You find some alternatives in the following link, Why don't gksu/gksudo or launching a graphical application with sudo work with Wayland?. A simple alternative is sudo -H GUI-application-program, but there are alternatives with higher security, for example pkexec. When you get used to text mode command lines (in terminal windows), you are no longer affected by this problem. – sudodus Apr 30 '18 at 11:10
  • 1
    pkexec with higher security accompanied by a higher probability of causing error messages, so test the app for error messages when using pkexec. – karel Apr 30 '18 at 11:25
  • 2
    Possible duplicate of How to fake a package version installed? – muru Apr 30 '18 at 12:47
  • Highly related: askubuntu.com/questions/1026800/… – Organic Marble Apr 30 '18 at 13:45
  • 2
    Close Voters: Initially I voted along with @muru duplicate candidate but retracted after reading Nobert's answer below which will server the OP much better because there will actually be a gksu app for the parent to call. Plus OP is satisfied and accepted answer. – WinEunuuchs2Unix May 1 '18 at 0:00


As Jeremy Bicha wrote:

Posted on April 18, 2018 by Jeremy Bicha — 8 Comments

Today, gksu was removed from Ubuntu 18.04, four weeks after it was removed from Debian.

So theoretically speaking there are no packages on Bionic Beaver 18.04 LTS, depending on gksu. But this is not true:

$ apt-cache rdepends gksu
Reverse Depends:

$ aptitude why gksu 
i   menu Suggests gksu | kde-runtime | ktsuss

As you see some software, which are distibuted by third-party may depend on gksu package. So you can proceed installing gksu with method below on your own risk.

How to fix?

Possible solution is to install version from previous (17.10, artful) release.

Warning: do not execute the commands below if unsure!

* Short method (as @MK suggested)

wget http://mirrors.kernel.org/ubuntu/pool/universe/libg/libgksu/libgksu2-0_2.0.13~pre1-9ubuntu2_amd64.deb
sudo apt install ./libgksu2-0_2.0.13~pre1-9ubuntu2_amd64.deb

wget http://mirrors.kernel.org/ubuntu/pool/universe/g/gksu/gksu_2.0.2-9ubuntu1_amd64.deb
sudo apt install ./gksu_2.0.2-9ubuntu1_amd64.deb

* Long method

  1. Add artful repositories to the system:

    cat <<EOF | sudo tee /etc/apt/sources.list.d/artful.list
    deb http://archive.ubuntu.com/ubuntu/ artful universe
  2. Update package cache

    sudo apt-get update
  3. Install gksu package

    sudo apt-get install gksu
  4. Remove artful repository from system for safety

    sudo rm /etc/apt/sources.list.d/artful.list
    sudo apt-get update


Test gksu (should work on Xorg-sessions)

gksu-properties # check that it has "Authentication mode" to "sudo"
gksu date
gksudo date


After installation the following packages will be marked as obsolete (locally-installed): gksu, libgksu2-0. But they will work as expected.

  • 1
    brilliant, I worked like Magic !!! thanks a lot – Abdelaziz Mokhnache Apr 30 '18 at 12:19
  • just to be sure, won't I have issues in the future having gksu installed on 18.04 ? or I have to remove it after I am done with App installation ? – Abdelaziz Mokhnache Apr 30 '18 at 12:21
  • 1
    @N0rbert: Instead of adding the whole shabang, which you admit is dangerous, you can just download the lib .deb from packages.ubuntu.com/artful/amd64/libgksu2-0/download and the gksu .deb file from launchpad.net/ubuntu/bionic/amd64/gksu/2.0.2-9ubuntu1. Install the lib first using gdebi, followed by the gksu, also using gedbi – M K May 9 '18 at 11:10
  • @MK, thanks, I added your method to the answer. – N0rbert May 14 '18 at 19:12
  • Running with mixed repositories is a horrible idea. If you must, at least set up Apt Pinning. – xiota May 31 '18 at 2:18

Mixed repositories

Adding the artful repositories to a bionic system is an absolutely horrible idea. I cannot stress enough how much suffering the notion, alone, of running with mixed repositories will bring. There shall be misery and gnashing of teeth to the end of the age and beyond.

Masochists, please at least use protection (Apt Pinning).

Better ideas


  • kdesudo has been dropped as well.

  • lxqt-sudo is still around, but didn't work for me.

  • Something called gosa? No idea what it is.

  • Might as well play sudoku until this mess is figured out.

protected by N0rbert Nov 27 '18 at 21:08

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