# ubuntu Issues related to Ubuntu OS or related distributions ## apt errors If you want to delete an wrong or non-working repository you can listed and delete by going to: ``` $ cd /etc/apt/sources.list.d $ ls docker.list elementary.list owncloud.list patches.list ``` then just remove the non wanted `.list` directory by: ``` $ sudp rm owncloud.list ``` considering that we want to delete the `owncloud` repository. Other for to do it is by using the `apt-key del` command, if there is a gpg reposotory. Thus, first we need to list the repositories to determine which will be removed: ``` $ sudo apt-key list /etc/apt/trusted.gpg -------------------- pub rsa2048 2015-09-28 [SC] [expires: 2022-05-28] 06D7 EADE 708A 40FA 136E B454 0700 205D FD41 A71A uid [ unknown] devel OBS Project /etc/apt/trusted.gpg.d/elementary.key.asc ----------------------------------------- pub rsa1024 2011-10-01 [SC] 6C87 69CE DC20 F5E6 6C3B 7D37 BF36 996C 4E1F 8A59 uid [ unknown] Launchpad PPA for elementary OS team ``` in this case we will delete the owncloud repository `06D7 EADE 708A 40FA 136E B454 0700 205D FD41 A71A` by using: ``` $ sudo apt-key del "06D7 EADE 708A 40FA 136E B454 0700 205D FD41 A71A" OK $ sudo apt-get update ```