Error fix
How to fix “APT Installation Error: 404 Not Found”
The package manager cannot find the requested packages on the specified repository.
Updated Apr 20, 2026
Tools that help with this
Fastest fix
Start here first. Step 1 fixes most cases—then work down the list.
- Edit sources.list to use a different mirror.
- Run sudo apt update.
- Retry the installation command.
What this means
The error indicates that the APT package manager is trying to fetch packages from a repository that no longer has the requested files available. This typically happens when the repository is outdated or has been removed.
Common causes
Outdated Repository
The repository URL may point to an old or deprecated version of Ubuntu.
Incorrect Mirror
The mirror server may not have the required packages or may be misconfigured.
Step-by-step fix
Change Repository URL
- Open the sources list with: sudo nano /etc/apt/sources.list
- Replace 'http://mirrors.linode.com/ubuntu' with 'http://archive.ubuntu.com/ubuntu'
- Save the file and exit.
Update Package List
- Run: sudo apt update
- Then try installing again with: sudo apt install certbot python3-certbot-apache
Related
FAQ
- What does a 404 error mean in APT?
- It means that the requested package or repository could not be found.
- How do I find a working mirror for Ubuntu?
- You can check the official Ubuntu mirror list at https://launchpad.net/ubuntu/+archivemirrors.
- What should I do if I still see 404 errors?
- Ensure your sources.list file is correctly configured and points to supported repositories.
- Can I use a different package manager?
- Yes, you can use other package managers like snap or flatpak for certain applications.
Developer notes
Consider using a more stable mirror or the official Ubuntu repository for better reliability.
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Full error text (logs / stack trace)
root@swshingles:~# sudo apt install certbot python3-certbot-apache Reading package lists... Done Building dependency tree... Done Reading state information... Done The following additional packages will be installed: augeas-lenses libaugeas0 python3-acme python3-augeas python3-certbot python3-configargparse python3-icu python3-josepy python3-parsedatetime python3-rfc3339 Suggested packages: augeas-doc python-certbot-doc python3-certbot-nginx augeas-tools python-acme-doc python-certbot-apache-doc The following NEW packages will be installed: augeas-lenses certbot libaugeas0 python3-acme python3-augeas python3-certbot python3-certbot-apache python3-configargparse python3-icu python3-josepy python3-parsedatetime python3-rfc3339 0 upgraded, 12 newly installed, 0 to remove and 53 not upgraded. Need to get 1,478 kB of archives. After this operation, 7,098 kB of additional disk space will be used. Do you want to continue? [Y/n] y Err:1 http://mirrors.linode.com/ubuntu lunar/universe amd64 augeas-lenses all 1.14.0-1 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] Err:2 http://mirrors.linode.com/ubuntu lunar/universe amd64 libaugeas0 amd64 1.14.0-1 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] Err:3 http://mirrors.linode.com/ubuntu lunar/universe amd64 python3-josepy all 1.13.0-1 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] Get:4 http://mirrors.linode.com/ubuntu lunar/universe amd64 python3-rfc3339 all 1.1-4 [6,744 B] Err:5 http://mirrors.linode.com/ubuntu lunar/universe amd64 python3-acme all 2.1.0-1 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] Get:6 http://mirrors.linode.com/ubuntu lunar/universe amd64 python3-augeas all 0.5.0-1.1 [9,124 B] Get:7 http://mirrors.linode.com/ubuntu lunar/universe amd64 python3-configargparse all 1.5.3-1 [26.9 kB] Get:8 http://mirrors.linode.com/ubuntu lunar/universe amd64 python3-parsedatetime all 2.6-3 [32.8 kB] Err:9 http://mirrors.linode.com/ubuntu lunar/universe amd64 python3-certbot all 2.1.0-4 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] Err:10 http://mirrors.linode.com/ubuntu lunar/universe amd64 certbot all 2.1.0-4 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] Err:11 http://mirrors.linode.com/ubuntu lunar/universe amd64 python3-certbot-apache all 2.1.0-2 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] Err:12 http://mirrors.linode.com/ubuntu lunar/main amd64 python3-icu amd64 2.10.2-1build2 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] Fetched 75.5 kB in 0s (235 kB/s) E: Failed to fetch http://mirrors.linode.com/ubuntu/pool/universe/a/augeas/augeas-lenses_1.14.0-1_all.deb 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] E: Failed to fetch http://mirrors.linode.com/ubuntu/pool/universe/a/augeas/libaugeas0_1.14.0-1_amd64.deb 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] E: Failed to fetch http://mirrors.linode.com/ubuntu/pool/universe/p/python-josepy/python3-josepy_1.13.0-1_all.deb 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] E: Failed to fetch http://mirrors.linode.com/ubuntu/pool/universe/p/python-acme/python3-acme_2.1.0-1_all.deb 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] E: Failed to fetch http://mirrors.linode.com/ubuntu/pool/universe/p/python-certbot/python3-certbot_2.1.0-4_all.deb 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] E: Failed to fetch http://mirrors.linode.com/ubuntu/pool/universe/p/python-certbot/certbot_2.1.0-4_all.deb 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] E: Failed to fetch http://mirrors.linode.com/ubuntu/pool/universe/p/python-certbot-apache/python3-certbot-apache_2.1.0-2_all.deb 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] E: Failed to fetch http://mirrors.linode.com/ubuntu/pool/main/p/pyicu/python3-icu_2.10.2-1build2_amd64.deb 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing? root@swshingles:~# sudo apt update Ign:1 http://mirrors.linode.com/ubuntu lunar InRelease Ign:2 http://mirrors.linode.com/ubuntu lunar-updates InRelease Ign:3 http://mirrors.linode.com/ubuntu lunar-backports InRelease Err:4 http://mirrors.linode.com/ubuntu lunar Release 404 Not Found [IP: 2600:1404:ec00:3d::17dc:618b 80] Err:5 http://mirrors.linode.com/ubuntu lunar-updates Release 404 Not Found [IP: 2600:1404:ec00:3d::17dc:618b 80] Err:6 http://mirrors.linode.com/ubuntu lunar-backports Release 404 Not Found [IP: 2600:1404:ec00:3d::17dc:618b 80] Ign:7 http://security.ubuntu.com/ubuntu lunar-security InRelease Err:8 http://security.ubuntu.com/ubuntu lunar-security Release 404 Not Found [IP: 2620:2d:4000:1::102 80] Reading package lists... Done E: The repository 'http://mirrors.linode.com/ubuntu lunar Release' no longer has 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. E: The repository 'http://mirrors.linode.com/ubuntu lunar-updates Release' no longer has 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. E: The repository 'http://mirrors.linode.com/ubuntu lunar-backports Release' no longer has 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. E: The repository 'http://security.ubuntu.com/ubuntu lunar-security Release' no longer has 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. root@swshingles:~# sudo apt install certbot python3-certbot-apache Reading package lists... Done Building dependency tree... Done Reading state information... Done The following additional packages will be installed: augeas-lenses libaugeas0 python3-acme python3-augeas python3-certbot python3-configargparse python3-icu python3-josepy python3-parsedatetime python3-rfc3339 Suggested packages: augeas-doc python-certbot-doc python3-certbot-nginx augeas-tools python-acme-doc python-certbot-apache-doc The following NEW packages will be installed: augeas-lenses certbot libaugeas0 python3-acme python3-augeas python3-certbot python3-certbot-apache python3-configargparse python3-icu python3-josepy python3-parsedatetime python3-rfc3339 0 upgraded, 12 newly installed, 0 to remove and 53 not upgraded. Need to get 1,402 kB/1,478 kB of archives. After this operation, 7,098 kB of additional disk space will be used. Do you want to continue? [Y/n] y Err:1 http://mirrors.linode.com/ubuntu lunar/universe amd64 augeas-lenses all 1.14.0-1 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] Err:2 http://mirrors.linode.com/ubuntu lunar/universe amd64 libaugeas0 amd64 1.14.0-1 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] Err:3 http://mirrors.linode.com/ubuntu lunar/universe amd64 python3-josepy all 1.13.0-1 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] Err:4 http://mirrors.linode.com/ubuntu lunar/universe amd64 python3-acme all 2.1.0-1 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] Err:5 http://mirrors.linode.com/ubuntu lunar/universe amd64 python3-certbot all 2.1.0-4 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] Err:6 http://mirrors.linode.com/ubuntu lunar/universe amd64 certbot all 2.1.0-4 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] Err:7 http://mirrors.linode.com/ubuntu lunar/universe amd64 python3-certbot-apache all 2.1.0-2 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] Err:8 http://mirrors.linode.com/ubuntu lunar/main amd64 python3-icu amd64 2.10.2-1build2 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] E: Failed to fetch http://mirrors.linode.com/ubuntu/pool/universe/a/augeas/augeas-lenses_1.14.0-1_all.deb 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] E: Failed to fetch http://mirrors.linode.com/ubuntu/pool/universe/a/augeas/libaugeas0_1.14.0-1_amd64.deb 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] E: Failed to fetch http://mirrors.linode.com/ubuntu/pool/universe/p/python-josepy/python3-josepy_1.13.0-1_all.deb 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] E: Failed to fetch http://mirrors.linode.com/ubuntu/pool/universe/p/python-acme/python3-acme_2.1.0-1_all.deb 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] E: Failed to fetch http://mirrors.linode.com/ubuntu/pool/universe/p/python-certbot/python3-certbot_2.1.0-4_all.deb 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] E: Failed to fetch http://mirrors.linode.com/ubuntu/pool/universe/p/python-certbot/certbot_2.1.0-4_all.deb 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] E: Failed to fetch http://mirrors.linode.com/ubuntu/pool/universe/p/python-certbot-apache/python3-certbot-apache_2.1.0-2_all.deb 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] E: Failed to fetch http://mirrors.linode.com/ubuntu/pool/main/p/pyicu/python3-icu_2.10.2-1build2_amd64.deb 404 Not Found [IP: 2600:1404:ec00:3d::17dc:61c9 80] E: Unable to fetch some archives, maybe run apt-get update or try with --fix-missing? root@swshingles:~# apt-get update Ign:1 http://mirrors.linode.com/ubuntu lunar InRelease Ign:2 http://mirrors.linode.com/ubuntu lunar-updates InRelease Ign:3 http://mirrors.linode.com/ubuntu lunar-backports InRelease Err:4 http://mirrors.linode.com/ubuntu lunar Release 404 Not Found [IP: 2600:1404:ec00:3d::17dc:618b 80] Err:5 http://mirrors.linode.com/ubuntu lunar-updates Release 404 Not Found [IP: 2600:1404:ec00:3d::17dc:618b 80] Err:6 http://mirrors.linode.com/ubuntu lunar-backports Release 404 Not Found [IP: 2600:1404:ec00:3d::17dc:618b 80] Ign:7 http://security.ubuntu.com/ubuntu lunar-security InRelease Err:8 http://security.ubuntu.com/ubuntu lunar-security Release 404 Not Found [IP: 2620:2d:4000:1::103 80] Reading package lists... Done E: The repository 'http://mirrors.linode.com/ubuntu lunar Release' no longer has 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. E: The repository 'http://mirrors.linode.com/ubuntu lunar-updates Release' no longer has 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. E: The repository 'http://mirrors.linode.com/ubuntu lunar-backports Release' no longer has 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. E: The repository 'http://security.ubuntu.com/ubuntu lunar-security Release' no longer has 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.