Are you getting either the “Missing Signed-By in the sources.list” N error or, a W error “uses weak algorithm” error? Both of these messages can be resolved with the two steps below – delete ondrej sources files, re-add the ondrej repository.
We’re talking bout Ubuntu 24.4 Noble Numbat here.
Results from checking apt get updates. Weak Algorithm. Doesn’t sound good. Launchpad. Abort.
- W: http://ppa.launchpad.net/ondrej/php/ubuntu/dists/noble/InRelease: Signature by key 14AA40EC0831756756D7F66C4F4EA0AAE5267A6C uses weak algorithm (rsa1024)
- N: Missing Signed-By in the sources.list(5) entry for ‘http://ppa.launchpad.net/ondrej/php/ubuntu’
For fun. Run the apt remove command. It will likely fail, that’s why you’re here.
- sudo add-apt-repository –remove ppa:ondrej/php (ondrej’s like no please man don’t do that, please, ok)
Delete the following two files from /etc/apt/sources.list.d – mine had names as thus
- ondrej-ubuntu-php-focal.list.distUpgrade
- ondrej-ubuntu-php-focal.sources
Run the apt install command!
- sudo add-apt-repository ppa:ondrej/php
Run an update. No weak keys in my house!
- We’re all PPA’d up

