Err:1 http://security.ubuntu.com/ubuntu bionic-security InRelease
403 Forbidden [IP: 91.189.91.26 80]
Err:2 http://ppa.launchpad.net/gnome3-team/gnome3-staging/ubuntu bionic InRelease
403 Forbidden [IP: 91.189.95.83 80]
Err:3 http://ppa.launchpad.net/nathan-renniewaldock/flux/ubuntu bionic InRelease
403 Forbidden [IP: 91.189.95.83 80]
Err:4 http://ppa.launchpad.net/ubuntu-wine/ppa/ubuntu bionic InRelease
403 Forbidden [IP: 91.189.95.83 80]
Err:5 http://ppa.launchpad.net/webupd8team/y-ppa-manager/ubuntu bionic InRelease
403 Forbidden [IP: 91.189.95.83 80]
Err:6 http://archive.ubuntu.com/ubuntu bionic InRelease
403 Forbidden [IP: 91.189.88.162 80]
Err:7 http://archive.ubuntu.com/ubuntu bionic-updates InRelease
403 Forbidden [IP: 91.189.88.162 80]
Err:8 http://archive.ubuntu.com/ubuntu bionic-backports InRelease
403 Forbidden [IP: 91.189.88.162 80]
Reading package lists... Done
N: See apt-secure(8) manpage for repository creation and user configuration details.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
E: The repository 'http://security.ubuntu.com/ubuntu bionic-security InRelease' is not signed.
E: Failed to fetch http://security.ubuntu.com/ubuntu/dists/bionic-security/InRelease 403 Forbidden [IP: 91.189.91.26 80]
N: See apt-secure(8) manpage for repository creation and user configuration details.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
E: The repository 'http://ppa.launchpad.net/gnome3-team/gnome3-staging/ubuntu bionic InRelease' is not signed.
E: Failed to fetch http://ppa.launchpad.net/gnome3-team/gnome3-staging/ubuntu/dists/bionic/InRelease 403 Forbidden [IP: 91.189.95.83 80]
N: See apt-secure(8) manpage for repository creation and user configuration details.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
E: The repository 'http://ppa.launchpad.net/nathan-renniewaldock/flux/ubuntu bionic InRelease' is not signed.
E: Failed to fetch http://ppa.launchpad.net/nathan-renniewaldock/flux/ubuntu/dists/bionic/InRelease 403 Forbidden [IP: 91.189.95.83 80]
N: See apt-secure(8) manpage for repository creation and user configuration details.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
E: The repository 'http://ppa.launchpad.net/ubuntu-wine/ppa/ubuntu bionic InRelease' is not signed.
E: Failed to fetch http://ppa.launchpad.net/ubuntu-wine/ppa/ubuntu/dists/bionic/InRelease 403 Forbidden [IP: 91.189.95.83 80]
N: See apt-secure(8) manpage for repository creation and user configuration details.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
E: The repository 'http://ppa.launchpad.net/webupd8team/y-ppa-manager/ubuntu bionic InRelease' is not signed.
E: Failed to fetch http://ppa.launchpad.net/webupd8team/y-ppa-manager/ubuntu/dists/bionic/InRelease 403 Forbidden [IP: 91.189.95.83 80]
N: See apt-secure(8) manpage for repository creation and user configuration details.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
E: The repository 'http://archive.ubuntu.com/ubuntu bionic InRelease' is not signed.
E: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/bionic/InRelease 403 Forbidden [IP: 91.189.88.162 80]
E: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/bionic-updates/InRelease 403 Forbidden [IP: 91.189.88.162 80]
E: The repository 'http://archive.ubuntu.com/ubuntu bionic-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.
E: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/bionic-backports/InRelease 403 Forbidden [IP: 91.189.88.162 80]
E: The repository 'http://archive.ubuntu.com/ubuntu bionic-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.
enter code here
答案1
这些 URL 有效，请尝试使用浏览器（从同一网络）访问其中一个，例如：
http://archive.ubuntu.com/ubuntu/dists/bionic-updates/InRelease
如果您在浏览器中也收到 403 错误，则最可能的原因是（透明）代理拒绝访问该资源。