How can I fix a 404 Error using a PPA?

Question

PPA seems to be constantly offline.

Err `http://ppa.launchpad.net` oneiric/main Sources                    
404  Not Found

Ign `http://security.ubuntu.com` oneiric-security/universe Translation-en

Err `http://ppa.launchpad.net` oneiric/main amd64 Packages 
404  Not Found

Err `http://ppa.launchpad.net` oneiric/main i386 Packages  
404  Not Found

Hit `http://us.archive.ubuntu.com` oneiric-backports Release.gpg

Err `http://ppa.launchpad.net` oneiric/main Sources                   
404  Not Found

Err `http://ppa.launchpad.net` oneiric/main amd64 Packages   
404  Not Found

Err `http://ppa.launchpad.net` oneiric/main i386 Packages             
404  Not Found

Answer 1

Automated removal

skip to the bottom of this answer for a scripted way to remove offending software-sources

What are 404 errors

The 404 or Not Found error message is a HTTP standard response code indicating that the client was able to communicate with the server, but the server could not find what was requested.

The web site hosting server will typically generate "404 - Page Not Found" web page, when users attempts to follow a broken or dead link.

What are the causes of these errors in update-manager

Typically, three main areas cause these errors in update-manager

1. A user has just upgraded and has re-enabled a PPA software-source that no longer exists
2. A user has manually typed in a new software source incorrectly
3. A PPA was added, but the maintainer has subsequently deleted some/all of the PPA

where are these software-sources

PPAs typically are saved in one of two locations

1. /etc/apt/sources.list
2. in an appropriately named file with a .list file-extension in /etc/apt/sources.list.d/ for example webupd8team-jupiter-natty.list

This list file typically contains:

deb http://ppa.launchpad.net/webupd8team/jupiter/ubuntu oneiric main
# deb-src http://ppa.launchpad.net/webupd8team/jupiter/ubuntu oneiric main

Note a # at the front of a line of text means that it is commented out and is not checked by the package manager.

How to eliminate these errors

Typically, if you run sudo apt-get update from a terminal or click the details button in Update Manager after hitting the refresh button you will see errors such as:

If the error is due to a PPA - usually unticking the similarly named PPA with the URL shown in the error message will resolve this.

If the 404 error was due to an additional repository that has been added to /etc/apt/sources.list then its easier to add # character to the start of the line to comment out the offending repository i.e.

gksu gedit /etc/apt/sources.list

Scripted removal

I've written a quick script that checks for PPAs and Software-Sources that exhibit the 404 errors.

Its in my PPA:

sudo add-apt-repository ppa:fossfreedom/packagefixes
sudo apt-get update
sudo apt-get install banish404

You can just download the deb package and install that directly:

wget https://launchpad.net/~fossfreedom/+archive/packagefixes/+files/banish404_0.1-4_all.deb
sudo dpkg -i banish404_0.1-4_all.deb

N.B. its the same deb package for all distributions.

Questions/Comments/Improvement please via Launchpad Contact Me link

How to use:

sudo banish404

The script will automatically backup of your sources before modification - to be found in /etc/apt

Answer 2

I get the following:

 jjack@jack:~$ sudo apt-get update | grep Err

Err http://ppa.launchpad.net oneiric/main Sources  
Err http://ppa.launchpad.net oneiric/main i386 Packages 
Err http://ppa.launchpad.net oneiric/main Sources 
Err http://ppa.launchpad.net oneiric/main i386 Packages 
W: Failed to fetch http://ppa.launchpad.net/bisigi/ppa/ubuntu/dists/oneiric/main/source/Sources  404  Not Found
W: Failed to fetch http://ppa.launchpad.net/bisigi/ppa/ubuntu/dists/oneiric/main/binary-i386/Packages  404  Not Found
W: Failed to fetch http://ppa.launchpad.net/sun-java-community-team/sun-java6/ubuntu/dists/oneiric/main/source/Sources  404  Not Found
W: Failed to fetch http://ppa.launchpad.net/sun-java-community-team/sun-java6/ubuntu/dists/oneiric/main/binary-i386/Packages  404  Not Found

E: Some index files failed to download. They have been ignored, or old ones used instead.

Somehow, there are eight ppa's, although there are only four errors-

I removed several unnecessary ppa .list and .list.save files from /etc/apt/sources.list.d

jjack@jack:~$ cd /etc/apt/sources.list.d

jjack@jack:/etc/apt/sources.list.d$ ls
bisigi-ppa-oneiric.list          chromium-daily-ppa-oneiric.list.save  ricotz-testing-oneiric.list                     sun-java-community-team-sun-java6-oneiric.list.save
bisigi-ppa-oneiric.list.save     gnome3-team-gnome3-oneiric.list       ricotz-testing-oneiric.list.save                victored-ambiance-evolution-oneiric.list
chromium-daily-ppa-oneiric.list  gnome3-team-gnome3-oneiric.list.save  sun-java-community-team-sun-java6-oneiric.list  victored-ambiance-evolution-oneiric.list.save


jjack@jack:/etc/apt/sources.list.d$ sudo rm bisigi-ppa-oneiric.list && rm bisigi-ppa-oneiric.list.save && rm sun-java-community-team-sun-java6-oneiric.list.save && rm sun-java-community-team-suun-java6-oneiric.list

[sudo] password for jjack: 

rm: remove write-protected regular file `bisigi-ppa-oneiric.list.save'? y
rm: cannot remove `bisigi-ppa-oneiric.list.save': Permission denied

The list.save should be deleted from recovery, but is not necessary to fix the update:

jjack@jack:/etc/apt/sources.list.d$ ls
bisigi-ppa-oneiric.list.save          gnome3-team-gnome3-oneiric.list       ricotz-testing-oneiric.list.save
chromium-daily-ppa-oneiric.list       gnome3-team-gnome3-oneiric.list.save  victored-ambiance-evolution-oneiric.list
chromium-daily-ppa-oneiric.list.save  ricotz-testing-oneiric.list           victored-ambiance-evolution-oneiric.list.save

And then,

jjack@jack:/etc/apt/sources.list.d$ sudo apt-get update

succeeds.

Answer 3

this answer guides you through removing a broken repository using the GUI. (I don't think adding screenshots adds value here: if you can't click on a named tab in the UI, no screenshot can help you)