For 7 months I have been using Elementary os.

I have been trying to take system updates.

But I have been having the following error no matter what I have done to get rid of it.

W: The repository 'http://ppa.launchpad.net/nvbn-rm/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/nvbn-rm/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.

I have seen that there are other people as well who are having the same problem. But since I am new in Linux a through help will be welcomed.

Thanks in advance

2 Answers 2


I don't think that's a standard repository; it's an add-on repository and the error means that there is no "Xenial" release for it. At some point you must have added this repository to add some software that wasn't supplied by Elementary. You should probably remove this PPA, otherwise it doesn't hurt leaving it because the error is specific to that PPA and not the rest of your system. Perform this at the command line to make sure your system is up to date and ignore the PPA error, sudo apt update && apt upgrade

  • Can you please more specific about removing that PPA? Piece of code will be really helpful. Jul 1, 2018 at 14:30
  • Well, first check your sources list. On Loki you should have 3 standard. Type this in console; ls /etc/apt/sources.list.d you should see these 3; appcenter.list, elementary.list, patches.list Delete the non-standard list, if present; sudo rm -i /etc/apt/sources.list.d/<bad.list> In your case it might be sudo rm -i /etc/apt/sources.list.d/nvbn.list, but I'm not sure. Feel free to reply on what your list sources say by that first command
    – Andrew
    Jul 12, 2018 at 15:55


The repository you tried to install on Loki doesn't support the version of Ubuntu Loki is based on

Loki is based on Ubuntu 16.04 codename xenial

To check in the future use:

  • To get your current ElementaryOS version codename

    • $ lsb_release -sc

    • for you should say loki

  • To get the codename of Ubuntu's version which your version of ElementaryOS is based on

    • $ lsb_release -scu

    • for you should say xenial

Everytime you look for apps, check if supports Ubuntu 16.04

Now the answer

There's at least three ways to remove a PPA: a manual way and two using some tools.

I'll present to you the easiest way:

  • Install
    • sudo apt install ppa-purge
  • Run
    • sudo ppa-purge ppa:nvbn-rm/ppa

If it doesn't help / doesn't work, tell me and I'll try to explain another method to be able to remove it


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