I tried adding this key by sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 40976EAF437D05B5
and then the update command gave me another error: root@pk:/var/www/html# apt-get update Get:1 http://security.ubuntu.com/ubuntu bionic-security InRelease [88.7 kB] Hit:2 http://archive.ubuntu.com/ubuntu bionic InRelease Hit:3 http://ppa.launchpad.net/ondrej/php/ubuntu bionic InRelease Ign:4 http://cz.archive.ubuntu.com/ubuntu precise InRelease Get:5 http://archive.ubuntu.com/ubuntu bionic-updates InRelease [88.7 kB] Get:6 http://cz.archive.ubuntu.com/ubuntu precise Release [49.6 kB] Get:7 http://cz.archive.ubuntu.com/ubuntu precise Release.gpg [198 B] Ign:7 http://cz.archive.ubuntu.com/ubuntu precise Release.gpg Reading package lists... Done W: GPG error: http://cz.archive.ubuntu.com/ubuntu precise Release: The following signatures were invalid: 630239CC130E1A7FD81A27B140976EAF437D05B5 E: The repository 'http://cz.archive.ubuntu.com/ubuntu precise Release' 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. -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1814803 Title: ubuntu 18.04 apt-get update key error the public key is not available: NO_PUBKEY 40976EAF437D05B5 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+bug/1814803/+subscriptions -- ubuntu-bugs mailing list [email protected] https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs
