I have been having a problem for a few day.

I can't upgrade linux (16.04LTS) anymore and I can't install packages. Here's what I get :
sudo apt-get update

I don't put everything because I am not allowed to post many links
E: Failed to fetch http://ppa.launchpad.net/jonathonf/python-3.6/ubuntu/dists/xenial/main/dep11/icons-64x64.tar 404 Not Found E: Some index files failed to download. They have been ignored, or old ones used instead.

sudo apt-get upgrade

Reading package lists... Done Building dependency tree
Reading state information... Done Calculating upgrade... Done The following packages have been kept back: debhelper 0 upgraded, 0 newly installed, 0 to remove and 1 not upgraded.

sudo apt-get install x11vnc

Reading package lists... Done Building dependency tree
Reading state information... Done E: Unable to locate package x11vnc remi@remi-Lenovo-G70-80:~$

Does anybody know what the problem is ?

  • ok but the subject points several possible origins, how t know which case is mine ? – Anoikis Nov 13 '17 at 22:03
  • Are you connected to the internet? ping -c 4 – NerdOfCode Nov 13 '17 at 23:26
  • how t know which case is mine Really?? It's right there in the error message (and if you keep messing with Python, adding PPAs or other things, you will break your system). – user692175 Nov 13 '17 at 23:35
  • So, the 404 error indicates a website not found, and specifically your error indicates that the repository at https://launchpad.net/~jonathonf/+archive/ubuntu/python-3.6 cannot be found. All of the answers in the referenced question deal with finding and removing unfound PPAs, by different methods - part of the bigger question is mentioned in JonathanF's PPA - did you remove or disable python3.5? – Charles Green Nov 14 '17 at 1:04

As a last resort, perhaps try removing all non-necessity sources from the /etc/apt/sources.list file, leaving only the essential ones for the system. By doing so this could possibly fix your issue. Before carrying out this action, I recommend creating a backup just in case you accidently delete something important...


You can create a backup simply by running cp sources.list sources.bak and if you accidently break something simply either move the copy or copy the copy back to the original by running cp sources.bak sources.list...

Hope this helps!!!Let me know

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  • Hello, Charles Green comment helped me. It works just fine now. Thanks a lot ! – Anoikis Nov 15 '17 at 21:00

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