E: The repository ‘http://download.owncloud.org/download/repositories/10.0/Ubuntu_18.04 Release’ no longer has a Release file. N: Updating from such a repository can’t be done securely, and is therefore disabled by default. N: See apt-secure(8) manpage for repository creation and user configuration details. You should be able to just remove the repo, as I recommend against upgrading using the package […]
