Today I get this message when trying to run
apt update on my Debian:
Hit:1 http://security.debian.org stretch/updates InRelease Ign:2 http://mirrors.digitalocean.com/debian stretch InRelease Hit:3 http://mirrors.digitalocean.com/debian stretch-updates InRelease Hit:4 http://mirrors.digitalocean.com/debian stretch Release Ign:5 http://ftp.debian.org/debian jessie-backports InRelease Err:6 http://ftp.debian.org/debian jessie-backports Release 404 Not Found [IP: 188.8.131.52 80] Get:7 http://deb.goaccess.io stretch InRelease [2,520 B] Get:8 https://packages.sury.org/php stretch InRelease [6,760 B] Hit:9 https://download.docker.com/linux/debian stretch InRelease Get:10 https://deb.nodesource.com/node_6.x stretch InRelease [4,635 B] Hit:11 https://repos.sonar.digitalocean.com/apt main InRelease Err:8 https://packages.sury.org/php stretch InRelease The following signatures couldn't be verified because the public key is not available: NO_PUBKEY B188E2B695BD4743 Reading package lists... Done E: The repository 'http://ftp.debian.org/debian jessie-backports Release' does no longer have a Release file. 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. W: An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: https://packages.sury.org/php stretch InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY B188E2B695BD4743
Any help will be much appreciated :)
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