Eu sou novo no Ubuntu e recebo este erro ao tentar uma atualização. Eu realmente aprecio isso, alguém poderia me ajudar. Obrigada!
W: GPG error: http://deb.playonlinux.com trusty InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 73F0D6E88E3D6C3A
W: The repository 'http://deb.playonlinux.com trusty InRelease' is not signed.
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.