sudo apt-get update [sudo] password for oliver: Hit:1 http://dl.google.com/linux/chrome/deb stable InRelease Hit:2 http://archive.canonical.com/ubuntu groovy InRelease Hit:3 http://repository.spotify.com stable InRelease Hit:4 http://ppa.launchpad.net/alexlarsson/flatpak/ubuntu disco InRelease Hit:5 http://packages.microsoft.com/repos/code stable InRelease Get:6 http://download.opensuse.org/repositories/home:/stevenpusser/xUbuntu_16.04 InRelease [1548 B] Ign:7 http://ppa.launchpad.net/gwendal-lebihan-dev/hexchat-stable/ubuntu groovy InRelease Hit:8 http://ppa.launchpad.net/quiterss/quiterss/ubuntu focal InRelease Hit:9 https://deb.opera.com/opera-stable stable InRelease Hit:10 http://de.archive.ubuntu.com/ubuntu groovy InRelease Hit:11 https://brave-browser-apt-release.s3.brave.com stable InRelease Hit:12 http://ppa.launchpad.net/vincent-vandevyvre/vvv/ubuntu eoan InRelease Hit:13 https://repo.skype.com/deb stable InRelease Get:14 http://de.archive.ubuntu.com/ubuntu groovy-updates InRelease [115 kB] Hit:15 https://ftp.gajim.org/debian unstable InRelease Err:16 http://ppa.launchpad.net/gwendal-lebihan-dev/hexchat-stable/ubuntu groovy Release 404 Not Found [IP: 91.189.95.85 80] Get:17 http://de.archive.ubuntu.com/ubuntu groovy-security InRelease [110 kB] Get:18 http://de.archive.ubuntu.com/ubuntu groovy-backports InRelease [101 kB] Err:6 http://download.opensuse.org/repositories/home:/stevenpusser/xUbuntu_16.04 InRelease The following signatures were invalid: EXPKEYSIG 0FAD31CA8719FCE4 home:stevenpusser OBS Project Get:19 http://de.archive.ubuntu.com/ubuntu groovy-updates/main amd64 Packages [434 kB] Get:20 http://de.archive.ubuntu.com/ubuntu groovy-updates/main i386 Packages [188 kB] Get:21 http://de.archive.ubuntu.com/ubuntu groovy-updates/main Translation-en [108 kB] Get:22 http://de.archive.ubuntu.com/ubuntu groovy-updates/main amd64 DEP-11 Metadata [40.6 kB] Get:23 http://de.archive.ubuntu.com/ubuntu groovy-updates/universe amd64 Packages [161 kB] Get:24 http://de.archive.ubuntu.com/ubuntu groovy-updates/universe i386 Packages [86.3 kB] Get:25 http://de.archive.ubuntu.com/ubuntu groovy-updates/universe Translation-en [63.0 kB] Get:26 http://de.archive.ubuntu.com/ubuntu groovy-updates/universe amd64 DEP-11 Metadata [103 kB] Get:27 http://de.archive.ubuntu.com/ubuntu groovy-updates/multiverse amd64 DEP-11 Metadata [2468 B] Get:28 http://de.archive.ubuntu.com/ubuntu groovy-security/main amd64 DEP-11 Metadata [4692 B] Get:29 http://de.archive.ubuntu.com/ubuntu groovy-security/universe amd64 DEP-11 Metadata [4548 B] Get:30 http://de.archive.ubuntu.com/ubuntu groovy-backports/universe amd64 DEP-11 Metadata [600 B] Reading package lists... Done E: The repository 'http://ppa.launchpad.net/gwendal-lebihan-dev/hexchat-stable/ubuntu groovy Release' does not have 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. W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://download.opensuse.org/repositories/home:/stevenpusser/xUbuntu_16.04 InRelease: The following signatures were invalid: EXPKEYSIG 0FAD31CA8719FCE4 home:stevenpusser OBS Project