I am new in ubuntu and i am trying to download ROS at the moment. the idea of repository keyrings are still new. However i am getting somewhere and making progress. this error seems to render my installation useless, please help me out of this. I have tried the ls/etc/apt/sources.list.d and rm files.. but nothing happened. the next message tells me to 'Manage keyring files in trusted.gpg.d instead' what to do please guide. thanks
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Setting up keys for a local repository on a new ubuntu 20.10 virtual machine, I got a message that apt-key add was deprecated and I should read the apt-key(8) man page. The apt-key(8) man page is a collection of words strung together, but if it contains information I can't winkle it out. Can anyone tell me what, exactly, I should type on my terminal instead of: apt-key add name-of-file The command does apparently still work after honking at me, so I was able to proceed, but would like to know what I'll need to do in the future.
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When I try to install any software, I encounter this error, and therefore I cannot update.  Preconfiguring packages ... dpkg: error: parsing file '/var/lib/dpkg/status' near line 51245 package 'oracle-xe':  mixed non-coinstallable and coinstallable package instances present N: Ignoring file 'gcl' in directory '/etc/apt/sources.list.d/' as it has no filename extension N: Ignoring file 'gcl' in directory '/etc/apt/sources.list.d/' as it has no filename extension E: Sub-process /usr/bin/dpkg returned an error code (2)
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When I check for updates, I get a "Failed To Download Repository Information" error.   This is what comes up under details:   W: Failed to fetch gzip:/var/lib/apt/lists/partial/us.archive.ubuntu.com_ubuntu_dists_natty_main_source_Sources  Hash Sum mismatch,  E: Some index files failed to download. They have been ignored, or old ones used instead.
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gpg: WARNING: unsafe permissions on configuration file `/home/david/.gnupg/gpg.conf' gpg: WARNING: unsafe enclosing directory permissions on configuration file `/home/david/.gnupg/gpg.conf' gpg: external program calls are disabled due to unsafe options file permissions gpg: keyserver communications error: general error gpg: keyserver receive failed: general error   What does it mean and how to fix?
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There are now errors when updating and I cannot install most software due to a corrupted  /etc/apt/sources.list   file. Is there a copy I can download to replace it?  The file would be for Ubuntu 12.04 (Final Beta) in the United States.
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The error I am having when trying to update my package list.  W: GPG error: http://download.opensuse.org ./ Release: The following signatures were invalid: KEYEXPIRED 1436387333  W: Failed to fetch http://ppa.launchpad.net/samrog131/ppa/ubuntu/dists/trusty/main/binary-amd64/Packages  404  Not Found  E: Some index files failed to download. They have been ignored, or old ones used instead.
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Whenever I click on software updater it says Failed to download repository information.  It's been saying this for the past few days now and I don't know why, my Internet connection is fine, I am able to manually download software.  Sometimes it crashes when I click okay, then attempts to look for updates again and gives me the same message.  Any ideas?  [EDIT] I just tried an answer posted where I reset where the downloads come from, but I was left with this message:  W:The repository 'http://ppa.launchpad.net/noobslab/noobslab-conky/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.,  W:https://content.runescape.com/downloads/ubuntu/dists/trusty/InRelease: Signature by key AAC9264309E4D717441DB9527373B12CE03BEB4B uses weak digest algorithm (SHA1),  E:Failed to fetch http://ppa.launchpad.net/noobslab/noobslab-conky/ubuntu/dists/xenial/main/binary-amd64/Packages  404  Not Found,  E:Some index files failed to download. They have been ignored, or old ones used instead.
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I am getting sudo errors, how do I fix this error?  sudo: /etc/sudoers is mode 0777, should be 0440 sudo: no valid sudoers sources found, quitting
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I'm using an unsigned repo in Ubuntu 16.04 from Debian multimedia:  deb http://www.deb-multimedia.org jessie main   To install deb-multimedia-keyring, I'm running:  apt-get update &amp;&amp; apt-get install deb-multimedia-keyring -y   This gives an error:  W: GPG error: http://www.deb-multimedia.org jessie InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 5C808C2B65558117 E: The repository 'http://www.deb-multimedia.org jessie InRelease' is not signed. 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.
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When I run sudo apt-get update I get the following error:  W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/trusty/main/binary-armhf/Packages  404  Not Found [IP: 91.189.91.15 80]  E: Some index files failed to download. They have been ignored, or old ones used instead.   I've tried looking in /etc/apt/sources.list.d/ to see if anything in that directory can be removed but all that is in there is  nodesource.list nodesource.list.save   In my sources.list file I have:  deb http://ports.ubuntu.com/ubuntu-ports/ trusty main deb-src http://ports.ubuntu.com/ubuntu-ports/ trusty main deb http://ports.ubuntu.com/ubuntu-ports/ trusty-updates main deb-src http://ports.ubuntu.com/ubuntu-ports/ trusty-updates main deb http://ports.ubuntu.com/ubuntu-ports/ trusty-security main deb-src http://ports.ubuntu.com/ubuntu-ports/ trusty-security main deb http://archive.ubuntu.com/ubuntu trusty main # deb-src http://archive.ubuntu.com/ubuntu trusty main   Can anyone recommend a way of fixing this error?
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Ubuntu noob here. I recently got a VPS running Ubuntu, and decided to install Chromium, my preferred browser, on it. After installation completed, I got a message stating that I cannot open Chromium with root privileges. How would I go about opening Chromium?
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This is exact content from my sources.list:  #  # deb cdrom:[Debian GNU/Linux 2016.1 _Kali-rolling_ - Official Snapshot amd64 LIVE/INSTALL Binary 20160830-11:29]/ kali-rolling contrib main non-free #deb cdrom:[Debian GNU/Linux 2016.1 _Kali-rolling_ - Official Snapshot amd64 LIVE/INSTALL Binary 20160830-11:29]/ kali-rolling contrib main non-free   I couldn't install the Synaptic package manager and was told to modify sources.list.  I googled a lot and added some repos into it and ran update and upgrade command only to see Kali crash... I had to recover it.  Please mention the exact content that should be there to ensure that Kali Linux works.
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I'm writing a program that needs to download GPG keys for various distributions to do unattended net installs. To do this securely and in an automated way, I need to download the key via HTTPS, which means "gpg --recv-keys" isn't an option. Other distributions (e.g., Fedora) make their keys available on their websites via HTTPS (e.g., ), but I can't find the Ubuntu key file anywhere on ubuntu.com. Does anyone know where I can get it via HTTPS?
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I used UNetbootin to make a bootable USB to install Ubuntu 10.4 TLS, during installation, at 55%, I got an error [errn5] or something like that, next time I rebooted, I checked the disk to see if there's errors, at the end it said " error in 1 file ", what now ? How do I fix it? How do I know which file?
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I am on Ubuntu and I have forgotten the password for my Gnome Keyring (yes, stupid me, I know). Any way I can get it back? I have already looked at , but it says it's not possible if my home directory is encrypted and unfortunately my home directory is encrypted.
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Whenever I try to do anything at all that requires my password it returns this:  u7ur7l3@ubuntu:~$ sudo sudo: /usr/lib/sudo/sudoers.so must be owned by uid 0 sudo: fatal error, unable to load plugins u7ur7l3@ubuntu:~$   So I can't install anything from the Software Center / package manager or run any commands in terminal that require my password. I can log in, but that's pretty much it.  I accidentally changed the permissions of some files, then changed some more trying to fix it :/. Now I'm completely lost as to what to do.  This is what happened when I tried to get sudo working again using pkexec:  u7ur7l3@ubuntu:~$ pkexec chown root /usr/lib/sudo/sudoers.so Error getting authority: Error initializing authority: Error calling StartServiceByName for org.freedesktop.PolicyKit1: GDBus.Error:org.freedesktop.DBus.Error.Spawn.ExecFailed: Failed to execute program /usr/lib/dbus-1.0/dbus-daemon-launch-helper: Success   u7ur7l3@ubuntu:~$ sudo ls sudo: /usr/lib/sudo/sudoers.so must be owned by uid 0 sudo: fatal error, unable to load plugins   And to change permissions I was using Root Actions as a dolphin service/ plugin thing, so history doesn't show me the permission changes.  I just realized that sounds don't work at all anymore. When I go into Phonon my default settings and playback devices aren't even there. Also I don't have the option to shutdown, I can only log out or leave.
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Whenever I try to install anything with the Ubuntu Software Center, the following error appears.     Failed to download repository information      Check your Internet connection.      E:Unable to parse package file /var/lib/apt/lists/partial/archive.ubuntu.com_ubuntu_dists_precise_multiverse_i18n_Index (1)