我正在使用 Ubuntu 22.04.3 LTS。尝试运行后sudo apt-get update，像往常一样，我遇到了以下错误消息：
Get:1 https://brave-browser-apt-release.s3.brave.com stable InRelease [7547 B]
Err:1 https://brave-browser-apt-release.s3.brave.com stable InRelease
At least one invalid signature was encountered.
Get:2 http://archive.ubuntumirror.dei.uc.pt/ubuntu jammy InRelease [270 kB]
Get:3 http://archive.ubuntumirror.dei.uc.pt/ubuntu jammy-updates InRelease [119 kB]
Get:4 http://archive.ubuntumirror.dei.uc.pt/ubuntu jammy-backports InRelease [109 kB]
Get:5 http://archive.ubuntumirror.dei.uc.pt/ubuntu jammy-security InRelease [110 kB]
Err:2 http://archive.ubuntumirror.dei.uc.pt/ubuntu jammy InRelease
At least one invalid signature was encountered.
Err:3 http://archive.ubuntumirror.dei.uc.pt/ubuntu jammy-updates InRelease
At least one invalid signature was encountered.
Err:4 http://archive.ubuntumirror.dei.uc.pt/ubuntu jammy-backports InRelease
At least one invalid signature was encountered.
Err:5 http://archive.ubuntumirror.dei.uc.pt/ubuntu jammy-security InRelease
At least one invalid signature was encountered.
Reading package lists... Done
W: GPG error: https://brave-browser-apt-release.s3.brave.com stable InRelease: At least one invalid signature was encountered.
E: The repository 'https://brave-browser-apt-release.s3.brave.com stable 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.
W: GPG error: http://archive.ubuntumirror.dei.uc.pt/ubuntu jammy InRelease: At least one invalid signature was encountered.
E: The repository 'http://archive.ubuntumirror.dei.uc.pt/ubuntu jammy 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.
W: GPG error: http://archive.ubuntumirror.dei.uc.pt/ubuntu jammy-updates InRelease: At least one invalid signature was encountered.
E: The repository 'http://archive.ubuntumirror.dei.uc.pt/ubuntu jammy-updates 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.
W: GPG error: http://archive.ubuntumirror.dei.uc.pt/ubuntu jammy-backports InRelease: At least one invalid signature was encountered.
E: The repository 'http://archive.ubuntumirror.dei.uc.pt/ubuntu jammy-backports 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.
W: GPG error: http://archive.ubuntumirror.dei.uc.pt/ubuntu jammy-security InRelease: At least one invalid signature was encountered.
E: The repository 'http://archive.ubuntumirror.dei.uc.pt/ubuntu jammy-security 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.
尝试时apt-key list：
daniel@bonnie:~$ apt-key list
create_gpg_home:trap:14: undefined signal: ABRT
如果我尝试通过软件更新程序更新软件，我会收到以下消息：
无法下载存储库信息 检查您的互联网连接。
我不确定到底发生了什么，我尝试在线搜索，但只发现一个与我类似的问题，但没有得到解答：
22.04 - 安装 docker 引擎后 apt 更新时出错
编辑 1：我也无法安装任何软件包
sudo apt-get -y install postgresql
Reading package lists... Done
Building dependency tree... Done
Reading state information... Done
E: Unable to locate package postgresql
编辑2：尝试将下载服务器更改为主服务器，仍然出现同样的错误。
答案1
显然我改变了我的 bash 符号链接，这导致了问题。
运行以下命令后，错误已修复：
sudo ln -sf /bin/dash /bin/sh/