Thank you for reporting this bug to Ubuntu. It relates to Zorin which is not Ubuntu, and the Ubuntu components reached EOL (end-of-life) on 27 January 2014 so the door closed to release-upgrade long ago for that release. This is not a bug, as it works until some time after EOL, after which you need to manually change the script for Ubuntu releases to point to old-releases yourself.
Ubuntu 18.10 (cosmic) reached end-of-life on July 18, 2019. Ubuntu 17.10 (artful) reached end-of-life on July 19, 2018. Ubuntu 17.04 (zesty) reached end-of-life on January 13, 2018. Ubuntu 16.10 (yakkety) reached end-of-life on July 20, 2017. Ubuntu 15.10 (wily) reached end-of-life on July 28, 2016. Ubuntu 15.04 (vivid) reached end-of-life on February 4, 2016. Ubuntu 14.10 (utopic) reached end-of-life on July 23, 2015. Ubuntu 14.04 (trusty) reached end-of-life on April 25, 2019. Ubuntu 13.10 (saucy) reached end-of-life on July 17, 2014. Ubuntu 13.04 (raring) reached end-of-life on January 27, 2014. Ubuntu 12.10 (quantal) reached end-of-life on May 16, 2014. Ubuntu 12.04 (precise) reached end-of-life on April 28, 2017. Ubuntu 11.10 (oneiric) reached end-of-life on May 9, 2013. Ubuntu 11.04 (natty) reached end-of-life on October 28, 2012. Ubuntu 10.10 (maverick) reached end-of-life on April 10, 2012. Ubuntu 10.04 (lucid) reached end-of-life on May 9, 2013. Ubuntu 9.10 (karmic) reached end-of-life on April 30, 2011. Ubuntu 9.04 (jaunty) reached end-of-life on October 23, 2010. Ubuntu 8.10 (intrepid) reached end-of-life on April 30, 2010. Ubuntu 8.04 (hardy) reached end-of-life on May 12, 2011. Ubuntu 7.10 (gutsy) reached end-of-life on April 18th, 2009. Ubuntu 7.04 (feisty) reached end-of-life on October 19, 2008. See this document for currently supported Ubuntu releases: https://wiki.ubuntu.com/Releases We appreciate that this bug may be old and you might not be interested in discussing it any more. But if you are then please upgrade to the latest Ubuntu version and re-test. If you then find the bug is still present in the newer Ubuntu version, please add a comment here telling us which new version it is in and change the bug status to Confirmed. ** Changed in: ubuntu-release-upgrader (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1839042 Title: Updater failed To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/ubuntu-release-upgrader/+bug/1839042/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
