Update manager won't install from un-authenticated sources

Question

My update manager shows updates available. When I click on install updates it shows the following and does not update.

The action would require the installation of packages from not authenticated sources.

in details:

accountsservice cups cups-bsd cups-client cups-common cups-ppdc empathy empathy-common libaccountsservice0 libcups2 libcupscgi1 libcupsdriver1 libcupsimage2 libcupsmime1 libcupsppdc1 nautilus-sendto-empathy scribus-trunk

How to get updates ?

Answer 1

To update from unauthenticated sources, use this command :

sudo apt-get update && sudo apt-get upgrade --allow-unauthenticated

See the Ubuntu manual page for apt-get to get more details about --allow-unauthenticated option

Answer 2

You can un-check updates in Update Manager use this to find which update is causing the problem and then re-install the PPA it comes from.

Also try sudo apt-get update in a Terminal to update your software sources.

Answer 3

If your list of updates is not too long and you want to upgrade just a specific item. You can also: => Leave you update manager window open and go to synaptic,

=> type in the name of the update needed from the update manager.

=> If your update doesn't appear, remember to sort the search results by clicking the ''installed version'' column header so that they appear at the top.

=> Click on the relevant items with the grey exclamation mark then right click and click mark for upgrade, then apply.

=> A warning will come that the packages are unauthenticated. Click the button to continue the install and your update will be installed.

Hope that helps someone!