AppCenter and sudo apt update with "failed to fetch update"

Question

The AppCenter is not updating. When I try to update on the AppCenter, I get:

W: Target Packages (main/binary-amd64/Packages) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: Target Packages (main/binary-all/Packages) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: Target Translations (main/i18n/Translation-en_US) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: Target Translations (main/i18n/Translation-en) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: Target Translations (main/i18n/Translation-pt) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: Target DEP-11 (main/dep11/Components-amd64.yml) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: Target DEP-11-icons (main/dep11/icons-64x64.tar) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://ppa.launchpad.net/kxstudio-debian/libs/ubuntu lucid InRelease: Clearsigned file isn't valid, got 'NODATA' (does the network require authentication?) E: http://ppa.launchpad.net/kxstudio-debian/libs/ubuntu lucid InRelease is not (yet) available (Clearsigned file isn't valid, got 'NODATA' (does the network require authentication?)) W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://ppa.launchpad.net/kxstudio-debian/kxstudio/ubuntu lucid InRelease: Clearsigned file isn't valid, got 'NODATA' (does the network require authentication?) E: http://ppa.launchpad.net/kxstudio-debian/kxstudio/ubuntu lucid InRelease is not (yet) available (Clearsigned file isn't valid, got 'NODATA' (does the network require authentication?)) W: The repository 'http://ppa.launchpad.net/nathandyer/vocal-daily/ubuntu xenial Release' does not have a Release file. W: Data from such a repository can't be authenticated and is therefore potentially dangerous to use. W: See apt-secure(8) manpage for repository creation and user configuration details. E: http://ppa.launchpad.net/kxstudio-debian/music/ubuntu lucid/main amd64 Packages is not (yet) available (Hash Sum mismatch) E: http://ppa.launchpad.net/kxstudio-debian/music/ubuntu lucid/main i386 Packages is not (yet) available () E: http://ppa.launchpad.net/nathandyer/vocal-daily/ubuntu xenial/main amd64 Packages is not (yet) available (403 Forbidden)

And with sudo apt update, I get:

Hit:1 http://pt.archive.ubuntu.com/ubuntu xenial InRelease Hit:2 http://pt.archive.ubuntu.com/ubuntu xenial-updates InRelease
Get:3 http://pt.archive.ubuntu.com/ubuntu xenial-backports InRelease [102 kB] Ign:4 http://dl.google.com/linux/chrome/deb stable InRelease
Hit:5 http://ppa.launchpad.net/deluge-team/ppa/ubuntu xenial InRelease
Hit:6 http://packages.elementary.io/appcenter xenial InRelease
Hit:7 http://dl.google.com/linux/chrome/deb stable Release
Get:8 http://security.ubuntu.com/ubuntu xenial-security InRelease [102 kB]
Hit:9 http://ppa.launchpad.net/elementary-os/stable/ubuntu xenial InRelease Hit:11 https://repo.skype.com/deb stable InRelease
Ign:12 https://mega.nz/linux/MEGAsync/xUbuntu_16.04 ./ InRelease
Hit:13 http://repository.spotify.com stable InRelease
Hit:14 http://ppa.launchpad.net/freetuxtv/freetuxtv-dev/ubuntu xenial InRelease Hit:15 http://repo.steampowered.com/steam precise InRelease
Hit:16 http://ppa.launchpad.net/kxstudio-debian/ubuntus/ubuntu xenial InRelease Hit:17 http://ppa.launchpad.net/kxstudio-debian/gcc5/ubuntu wily InRelease
Get:18 https://mega.nz/linux/MEGAsync/xUbuntu_16.04 ./ Release [988 B]
Hit:19 http://ppa.launchpad.net/kxstudio-debian/gcc5/ubuntu xenial InRelease Hit:20 http://ppa.launchpad.net/kxstudio-debian/gcc5-deps/ubuntu xenial InRelease Hit:22 http://ppa.launchpad.net/kxstudio-debian/libs/ubuntu lucid InRelease 0% [22 InRelease gpgv 101 kB] [Waiting for headers]Splitting up /var/lib/apt/lists/ppa.launchpad.net_kxstudio-debian_libs_ubuntu_dists_lucid_InRelease intErr:22 http://ppa.launchpad.net/kxstudio-debian/libs/ubuntu lucid InRelease Clearsigned file isn't valid, got 'NODATA' (does the network require authentication?) Hit:23 http://ppa.launchpad.net/kxstudio-debian/music/ubuntu lucid InRelease Hit:24 http://ppa.launchpad.net/kxstudio-debian/plugins/ubuntu lucid InRelease Hit:25 http://ppa.launchpad.net/kxstudio-debian/apps/ubuntu lucid InRelease Hit:26 http://ppa.launchpad.net/kxstudio-debian/kxstudio/ubuntu lucid InRelease 0% [26 InRelease gpgv 101 kB] [Connecting to ppa.launchpad.net (91.189.95.83Splitting up /var/lib/apt/lists/ppa.launchpad.net_kxstudio-debian_kxstudio_ubuErr:26 http://ppa.launchpad.net/kxstudio-debian/kxstudio/ubuntu lucid InRelease Clearsigned file isn't valid, got 'NODATA' (does the network require authentication?) Hit:27 http://ppa.launchpad.net/kxstudio-debian/libs/ubuntu trusty InRelease Hit:28 http://ppa.launchpad.net/kxstudio-debian/music/ubuntu trusty InRelease Hit:29 http://ppa.launchpad.net/kxstudio-debian/plugins/ubuntu trusty InRelease Hit:30 http://ppa.launchpad.net/kxstudio-debian/apps/ubuntu trusty InRelease Hit:31 http://ppa.launchpad.net/kxstudio-debian/kxstudio/ubuntu trusty InRelease Hit:32 http://ppa.launchpad.net/mathieu.leplatre/subtivals/ubuntu xenial InRelease Hit:33 http://ppa.launchpad.net/menulibre-dev/daily/ubuntu xenial InRelease Hit:34 http://ppa.launchpad.net/mixxx/mixxx/ubuntu xenial InRelease
Ign:35 http://ppa.launchpad.net/nathandyer/vocal-daily/ubuntu xenial InRelease Hit:36 http://ppa.launchpad.net/openshot.developers/ppa/ubuntu xenial InRelease Hit:37 http://ppa.launchpad.net/elementary-os/os-patches/ubuntu xenial InRelease Hit:38 http://ppa.launchpad.net/phablet-team/tools/ubuntu xenial InRelease
Ign:39 http://ppa.launchpad.net/kxstudio-debian/music/ubuntu lucid/main amd64 Packages Ign:40 http://ppa.launchpad.net/kxstudio-debian/music/ubuntu lucid/main i386 Packages Ign:41 http://ppa.launchpad.net/kxstudio-debian/music/ubuntu lucid/main Translation-en Err:42 http://ppa.launchpad.net/nathandyer/vocal-daily/ubuntu xenial Release 403 Forbidden Ign:39 http://ppa.launchpad.net/kxstudio-debian/music/ubuntu lucid/main amd64 Packages Ign:40 http://ppa.launchpad.net/kxstudio-debian/music/ubuntu lucid/main i386 Packages Ign:41 http://ppa.launchpad.net/kxstudio-debian/music/ubuntu lucid/main Translation-en Get:39 http://ppa.launchpad.net/kxstudio-debian/music/ubuntu lucid/main amd64 Packages [64,6 kB] Err:39 http://ppa.launchpad.net/kxstudio-debian/music/ubuntu lucid/main amd64 Packages Hash Sum mismatch Ign:41 http://ppa.launchpad.net/kxstudio-debian/music/ubuntu lucid/main Translation-en Reading package lists... Done
W: Target Packages (main/binary-amd64/Packages) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: Target Packages (main/binary-all/Packages) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: Target Translations (main/i18n/Translation-en_US) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: Target Translations (main/i18n/Translation-en) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: Target Translations (main/i18n/Translation-pt) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: Target DEP-11 (main/dep11/Components-amd64.yml) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: Target DEP-11-icons (main/dep11/icons-64x64.tar) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://ppa.launchpad.net/kxstudio-debian/libs/ubuntu lucid InRelease: Clearsigned file isn't valid, got 'NODATA' (does the network require authentication?) W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://ppa.launchpad.net/kxstudio-debian/kxstudio/ubuntu lucid InRelease: Clearsigned file isn't valid, got 'NODATA' (does the network require authentication?) E: The repository 'http://ppa.launchpad.net/nathandyer/vocal-daily/ubuntu xenial 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: Target Packages (main/binary-amd64/Packages) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: Target Packages (main/binary-all/Packages) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: Target Translations (main/i18n/Translation-en_US) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: Target Translations (main/i18n/Translation-en) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: Target Translations (main/i18n/Translation-pt) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: Target DEP-11 (main/dep11/Components-amd64.yml) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1 W: Target DEP-11-icons (main/dep11/icons-64x64.tar) is configured multiple times in /etc/apt/sources.list:54 and /etc/apt/sources.list.d/appcenter.list:1

Can anyone help me here? Thanks in advance.

Answer 1

It appears to me that the PPAs kxstudio-debian and nathandyer/vocal-daily are causing issues here. You might want to remove them.

To do so,

1. Go to Applications
2. Right click on Files and select New Window as Administrator.
3. Then navigate to /etc/apt/sources.list.d.
4. In this directory, delete anything that says kxstudio or nathandyer.
5. Then try running an update; it should work.

Obviously, this means that you will no longer receive updates for KXStudio and Vocal.

For KXStudio, you can try to add the PPA from scratch later. For Vocal, unless you are a tester, you can just purchase it from AppCenter.