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When I wanted to upgrade from Ubuntu 13.10 to 14.04 the update manager told me that there was an unresolvable problem with calculating the upgrade. In order to see more details I performed the following on the command line:

apt-get update
apt-get upgrade
apt-get dist-upgrade
apt-get install update-manager-core
do-release-upgrade

Now do-release-upgrade tells me that no newer version is available but the "about" box in the main menu tells me I am still on 13.10. I think the latter is right, as for instance in the "system settings" there is no way to select local menus, which is present in 14.04 (I tried with a DVD, and there it is).

Maybe the problem is related to the fact that "apt-get update" cannot get two resources called "saucy/InRelease" and "saucy/main/binary-i386/Packages" from the mirror (mirror.informatik.uni-mannheim.de; 404 not found). I would like to use a different mirror; how can I do that?

Any help appreciated, thanks in advance.

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marked as duplicate by Sneetsher, psusi, Eric Carvalho, Jorge Castro, BuZZ-dEE Jun 10 at 19:12

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1 Answer 1

To change your mirror there are 2 methods:

  1. Using System Settings > Software and Updates. On the main tab there is a drop down labeled "Download from:" and choose a mirror from that drop down.

  2. Edit the file /etc/apt/sources.list with root access e.g. from terminal:

    sudo nano /etc/apt/sources.list

    Once in there replace "http://mirror.informatik.uni-mannheim.de" with "http://archive.ubuntu.com/ubuntu" (to get the main Ubuntu repo), or you could pick one from the long list: https://launchpad.net/ubuntu/+archivemirrors

Then once done repeat the steps you listed in your question:

apt-get update
apt-get upgrade
apt-get dist-upgrade
apt-get install update-manager-core
do-release-upgrade
share|improve this answer
    
Thanks, I changed sources.list but I still get an error during "apt-get update": getting ppa.launchpad.net/screenlets/ppa/ubuntu/dists/saucy/main/… fails with a 404 status. This happens even if I change all occurrences of "saucy" in sources.list to "trusty". –  Renardo Jun 9 at 9:20
    
I tried an "update-manager -d" now, and it tells me that it does not support an upgrade from trusty to saucy. But I want to go in the opposite direction. What makes the update-manager think I want to downgrade? –  Renardo Jun 9 at 9:39
1  
I re-installed Ubuntu from scratch, so the problems are no longer reproducible. –  Renardo Jun 9 at 18:02

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