Byronj64 $ sudo add-apt-repository ppa:openlp-core/release<br> Official releases of OpenLP<br> More info: https://launchpad.net/~openlp-core/+archive/ubuntu/release<br>Press [ENTER] to continue or Ctrl-c to cancel adding it.<br><br>Hit:1 http://us.archive.ubuntu.com/ubuntu bionic InRelease<br>Hit:2 http://archive.canonical.com/ubuntu bionic InRelease <br>Hit:3 http://ppa.launchpad.net/obsproject/obs-studio/ubuntu bionic InRelease <br>Hit:4 http://us.archive.ubuntu.com/ubuntu bionic-updates InRelease <br>Hit:5 http://us.archive.ubuntu.com/ubuntu bionic-backports InRelease <br>Get:6 http://security.ubuntu.com/ubuntu bionic-security InRelease [88.7 kB] <br>Ign:7 http://ppa.launchpad.net/openlp-core/release/ubuntu bionic InRelease <br>Err:8 http://ppa.launchpad.net/openlp-core/release/ubuntu bionic Release <br> 404 Not Found [IP: 91.189.95.83 80]<br>Reading package lists... Done <br>E: The repository 'http://ppa.launchpad.net/openlp-core/release/ubuntu bionic Release' does not have a Release file.<br>N: Updating from such a repository can't be done securely, and is therefore disabled by default.<br>N: See apt-secure(8) manpage for repository creation and user configuration details.<br><br><br>