Note that this answer is a copy of the answer in this article.
Theres not much you can do about expired keys, but to get a new valid one. Seems easy but still there are some caveats.
Note that multiple keys have been distributed in the past: the global key and a key for each distribution. Also recommended code snippets in the past put the keys in different locations (/etc/apt/trusted.gpg and /etc/apt/trusted.gpg.d/[…]).
This tutorial will try to fix all possible issues and get apt to work again.
1. Keys embedded in
apt-key del <id> to remove the key. Find the id of the repo home:manuelschneid3r using
# apt-key list
Warning: apt-key is deprecated. Manage keyring files in trusted.gpg.d instead (see apt-key(8)).
pub rsa2048 2017-10-27 [SC] [expired: 2022-03-05]
A4B8 3CD0 5FDF 5C51 7848 2D4A 1488 BLAA E192 A257
uid [ expired] home:manuelschneid3r OBS Project <home:firstname.lastname@example.org>
# apt-key del "A4B8 3CD0 5FDF 5C51 7848 2D4A 1488 BLAA E192 A257"
2. Keys in
Remove any keys related to Albert in
/etc/apt/trusted.gpg.d/. Note that, depending on the snippet you used to install albert, this keys may have obscure names. If you used the snipped on the official software center at OBS, the file is likely to have the name
3. Sources list
apt will now refuse to work with the error
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY …
If you want to keep albert, you can fetch a new key now. This is exactly what you did when you initially installed albert. Visit the OBS software center for the code snippet.
If you dont need albert anymore, remove the repository from your sources by removing either the relevant line in
/etc/apt/sources.list or the file
/etc/apt/sources.list.d/home:manuelschneid3r.list, depending on how you installed albert.
You're done. Have fun using albert 🍻