Force update from unsigned repository Ubuntu 16.04
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I 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 && apt-get install deb-multimedia-keyring -y This give 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. Thanks in advance
apt repository aptitude
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