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I have trouble with updating a new installed elementary OS 0.3.1 Freya (64-bit) system. The software updater starts and after a while fails: "Failed to download repository information. Check your Internet connection". My Internet connection works fine.
When I click on the "settings" option in that message I got the "updates" tab with security updates checked and the others unchecked. When trying to check other options I ran into problems like described here and followed the advice to uncheck all double entries in the software-updater.
I followed also the advice from here to remove the cache with a
sudo rm /var/cache/apt/*.bin command
When I close the settings the system takes some time and then I got the message: "Not all updates can be installed Run a partial upgrade, to install as many updates as possible ..." when I click the option "Partial Upgrade" I get the message "Can not upgrade. An upgrade from 'freya' to 'trusty' is not supported with this tool."
When I open the Software Updater again and choose the "Continue" option this time I get a new message: "Updated software is available for this computer. Do you want to install it now? Under "Details of updates" there is a list of software with check-boxes. checked is:
LibreOffice Base, LibreOffice Impress, VLC Media Player, 7z und 7za Archivierungsprogramm, HTML-Syntaxprüfer, LibreOffice component for bulding da..., Video-Dekodierungs und Präsentation..., e Ubuntu base. and an info: 15,6 MB will be downloaded.
When I click on "Install now" for a short time a message window "installing" pops up to be replaced short after with a message "Requires installation of untrusted packages. This requires installing packages from unauthenticated sources." With the option "settings" I get again in the window/panel with settings and the problem mentioned before. With a click on "ok" the Software Updater just quits.
I also tried the solution mentioned here and run in terminal with root apt-get update (in fact I tried this before several times) But it did not help for me.
I got errormessages like this:
From Software Updater: W:Failed to fetch http://ppa.launchpad.net/elementary-os/stable/ubuntu/dists/freya/main/source/Sources 404 Not Found , W:Failed to fetch... , W:Failed to fetch http://de.archive.ubuntu.com/ubuntu/dists/trusty/Release Unable to find expected entry 'contrib/source/Sources' in Release file (Wrong sources.list entry or malformed file) , E:Some index files failed to download. They have been ignored, or old ones used instead. From apt-get update: W: Fehlschlag beim Holen von http://ppa.launchpad.net/elementary-os/stable/ubuntu/dists/freya/main/source/Sources 404 Not Found ... W: Fehlschlag beim Holen von http://ppa.launchpad.net/elementary-os/os-patches/ubuntu/dists/freya/main/binary-i386/Packages 404 Not Found E: Einige Indexdateien konnten nicht heruntergeladen werden. Sie wurden ignoriert oder alte an ihrer Stelle benutzt.
For a solution it maybe is of interest that I struggled a lot with dual-boot elementary os alongside a pre-installed Win7 on Acer TMP 645. Finally got it work with rEFInd Bootmanager renamed and replaced into the windows-bootmanager place (seems the firmware / microsoft bootmanager prevents linux from adding new bootloaders to the EFI and deletes them every time on restart).
I indeed installed extra software: rEFInd of course and some extra software through the software center yesterday. The error messages I get from apt-get point to http:// security.debian.org and to ppa.launchpad.net/elementary-os/stable/... Before the extra software installed yesterday I also tried to update/upgrate with apt-get and already got the error message for the ppa.launchpad.net/elementary-os/stabel/ branch. Since the name of the branch contains "elementary-os" I wounder if i could/should disable/uninstall these packages as suggest in an earlier answer to this questions on Software updater doesn't work anymore correctly . It seems to me pointing to the core part of the elementary distro?! And if I should so that - how could I do that?
note: I am well conneted to the internet, that is not the problem.
Thank you for any help and advice Olaf
I posted the content of apt-get update and of /etc/apt/sources.list to paste.ubuntu (see links in comments to this post)