when I updating with sudo apt-get update , I got this:

N: Ignoring file '20auto-upgrades.ucf-dist' in directory '/etc/apt/apt.conf.d/' as it has an invalid filename extension    
W: The repository 'http://ppa.launchpad.net/lucid-bleed/ppa/ubuntu xenial Release' does not have a Release file.    
N: Data from such a repository can't be authenticated and is therefore potentially dangerous to use.    
N: See apt-secure(8) manpage for repository creation and user configuration details.    
E: Failed to fetch http://ppa.launchpad.net/lucid-bleed/ppa/ubuntu/dists/xenial/main/binary-amd64/Packages  404  Not Found    
E: Some index files failed to download. They have been ignored, or old ones used instead.

my question is:

  1. What is this error and how do I understand it.

  2. What should I do to solve this problems.


1 Answer 1


That error is as a result of the of the file 20auto-upgrades being named 20auto-upgrades.ucf-dist in the /etc/apt/apt.conf.d/ folder.

To fix it open your terminal and enter this:

sudo mv 20auto-upgrades.ucf-dist 20auto-upgrades

Then do:

sudo apt update && sudo apt dist-upgrade
  • Technically, what you fixed was the notice, not the error.
    – muru
    Jan 7, 2017 at 6:35
  • yes its the notice and for the remaining's i have to wait for the ppa repositories muru :) Jan 7, 2017 at 8:11

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