Eu recentemente instalei o Ubuntu 16.04 na minha máquina, mas ao tentar executar o sudo apt-get update recebi a seguinte mensagem:
W: The repository 'http://ppa.launchpad.net/freyja-dev/unity-tweak-tool-daily/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 https://deb.opera.com/opera-stable/dists/stable/InRelease Connection timed out after 120000 milliseconds
E: Failed to fetch http://ppa.launchpad.net/freyja-dev/unity-tweak-tool-daily/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.
Após algumas pesquisas, achei que seria útil alterar meu espelho de download, mas depois de selecionar o espelho recomendado e tentar atualizar, recebo a mensagem de erro:
Failed to download repository information.Check your Internet connection.
com os seguintes detalhes:
W:The repository 'http://ppa.launchpad.net/freyja-dev/unity-tweak-tool-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.,
W:Failed to fetch https://deb.opera.com/opera-stable/dists/stable/InRelease Connection timed out after 120000 milliseconds
E:Failed to fetch http://ppa.launchpad.net/freyja-dev/unity-tweak-tool-daily/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.
Alguma ideia de como posso resolver este problema? Agradecemos antecipadamente.
O problema são os PPAs mencionados na mensagem de erro, e não os repositórios oficiais:
https://deb.opera.com/opera-stable/dists/stable/InRelease
http://ppa.launchpad.net/freyja-dev/unity-tweak-tool-daily/ubuntu/dists/xenial/main/binary-amd64/Packages
Desative ou remova-os completamente. Mudar o espelho não tem impacto algum.
Informações adicionais: Como posso corrigir um erro 404 ao usar um PPA ou atualizar minhas listas de pacotes?