Ubuntu – How to install software or upgrade from an old unsupported release

package-managementrelease-managementrepositorysupportupgrade

Recently I have installed an older version of Ubuntu on my old machine. Whenever I try to install any software, I get an error saying it couldn't be found:

$ sudo apt-get install vlc
Reading package lists... Done               
Building dependency tree       
Reading state information... Done    
E: Couldn't find package vlc

Best Answer

The repositories for older releases that are not supported (like 11.04, 11.10 and 13.04) get moved to an archive server. There are repositories available at http://old-releases.ubuntu.com.

The reason for this is that it is now out of support and no longer receiving updates and security patches.

I would urge you to consider a supported distribution. If your computer is too old in terms of memory or processor then you should consider a distribution such as Lubuntu or Xubuntu.

If you want to continue using an outdated release then edit /etc/apt/sources.list and change archive.ubuntu.com and security.ubuntu.com to old-releases.ubuntu.com.

You can do this with sed:

sudo sed -i -re 's/([a-z]{2}\.)?archive.ubuntu.com|security.ubuntu.com/old-releases.ubuntu.com/g' /etc/apt/sources.list

then update with:

sudo apt-get update && sudo apt-get dist-upgrade

Sometimes, it might be faster to create backups of your system and reinstall using supported release instead.

Source: Can I keep using Ubuntu 9.04 if it's outdated?

To upgrade to a new release:

Once you have performed the above steps to switch to the old-releases mirrors, update the Update Manager and then do do-release-upgrade:

sudo apt-get update
sudo apt-get install ubuntu-release-upgrader-core
sudo do-release-upgrade

See also EOLUpgrades - Community Help Wiki.

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