I have an Ubuntu 15.04 and every time I try to download something (using sudo apt-get install), it says:
Reading package lists... Done Building dependency tree Reading state information... Done Package <packagename> 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 '<packagename>' has no installation candidate
I have tried "sudo apt-get update" and it said at the end:
W: Failed to fetch http://ppa.launchpad.net/irie/blender/ubuntu/dists/vivid/main/binary-amd64/Packages 404 Not Found W: Failed to fetch http://ppa.launchpad.net/irie/blender/ubuntu/dists/vivid/main/binary-i386/Packages 404 Not Found E: Some index files failed to download. They have been ignored, or old ones used instead.
I have also checked whether all of the checkboxes from "Ubuntu Software" tab of the "Software and Updates" window have been selected, and tried "sudo apt-get upgrade", but none of them worked.
Also, here is my sources.list file, which seems fine:
# deb cdrom:[Ubuntu 15.04 _Vivid Vervet_ - Release amd64 (20150422)]/ vivid main restricted # See http://help.ubuntu.com/community/UpgradeNotes for how to upgrade to # newer versions of the distribution. deb http://old-releases.ubuntu.com/ubuntu vivid main restricted ## Major bug fix updates produced after the final release of the ## distribution. deb http://old-releases.ubuntu.com/ubuntu vivid-updates main restricted ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team. Also, please note that software in universe WILL NOT receive any ## review or updates from the Ubuntu security team. deb http://old-releases.ubuntu.com/ubuntu vivid universe deb http://old-releases.ubuntu.com/ubuntu vivid-updates universe ## N.B. software from this repository is ENTIRELY UNSUPPORTED by the Ubuntu ## team, and may not be under a free licence. Please satisfy yourself as to ## your rights to use the software. Also, please note that software in ## multiverse WILL NOT receive any review or updates from the Ubuntu ## security team. deb http://old-releases.ubuntu.com/ubuntu vivid multiverse deb http://old-releases.ubuntu.com/ubuntu vivid-updates multiverse ## N.B. software from this repository may not have been tested as ## extensively as that contained in the main release, although it includes ## newer versions of some applications which may provide useful features. ## Also, please note that software in backports WILL NOT receive any review ## or updates from the Ubuntu security team. deb http://old-releases.ubuntu.com/ubuntu vivid-backports main restricted universe multiverse deb http://old-releases.ubuntu.com/ubuntu vivid-security main restricted deb http://old-releases.ubuntu.com/ubuntu vivid-security universe deb http://old-releases.ubuntu.com/ubuntu vivid-security multiverse ## Uncomment the following two lines to add software from Canonical's ## 'partner' repository. ## This software is not part of Ubuntu, but is offered by Canonical and the ## respective vendors as a service to Ubuntu users. # deb http://archive.canonical.com/ubuntu vivid partner # deb-src http://archive.canonical.com/ubuntu vivid partner deb http://www.openprinting.org/download/printdriver/debian/ lsb3.2 contrib
Also, I know that there are other questions similar to this one, but none of the solutions worked for me.
As I saw, many people in the comments suggested that I change the 'archives.ubuntu.com' lines in the sources.list to 'old-releases.ubuntu.com' because I have an outdated Ubuntu version. I tried that and the same message pops up when I type 'sudo apt-get update' (some index files failed to download), and when I try to install a package the same thing happens.
Some other people in the comments suggested that I upgrade to a newer Ubuntu version, which I tried also (sudo do-release-upgrade), but at the end it says:
Cannot upgrade, an upgrade from 'vivid' to 'xenial' is not supported with this tool.
I've also tried upgrading using sudo do-release upgrade -d, but then it says:
Checking for a new Ubuntu release No new release found