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I have been trying to figure out what is going on when I run apt-get update. I've tried going through the sources file and also using the Ubuntu Tweak to clean the sources list, but nothing is working.
When I run apt-get update I get this:
Reading package lists... Done N: Skipping acquire of configured file 'main/binary-i386/Packages' as repository 'https://packages.microsoft.com/repos/vscode stable InRelease' doesn't support architecture 'i386' 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:/Horst3180/xUbuntu_16.04 Release: The following signatures were invalid: KEYEXPIRED 1496576244 W: The repository 'http://ppa.launchpad.net/tualatrix/ppa/ubuntu xenial Release' does not have a Release file. N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use. N: See apt-secure(8) manpage for repository creation and user configuration details. W: Failed to fetch http://download.opensuse.org/repositories/home:/Horst3180/xUbuntu_16.04/Release.gpg The following signatures were invalid: KEYEXPIRED 1496576244 E: Failed to fetch http://ppa.launchpad.net/tualatrix/ppa/ubuntu/dists/xenial/main/binary-amd64/Packages 404 Not Found W: Some index files failed to download. They have been ignored, or old ones used instead. W: Duplicate sources.list entry http://packages.microsoft.com/repos/vscode stable Release