I get the problem after a new install. I have my configurations file in Dropbox and my bookmarks in Chrome/Chromium. It's essential to me that it's easy to install these packages. Today I used the 2/9 daily and Software provided this message both at installation of Dropbox and Chromium. "Enable Third-party Software Source? Dropbox is provided by "ubuntu-artful-universe". This software source must be enabled to continue installation. Cancel Enable and Install." When I use Enable and Install I get the message "Unable to install Dropbox [system/packages/ubuntu-artful-universe/desktop/dropbox.desktop/*] E:Could not find the repository" However GNOME Packages installs OK and both Dropbox and Chromium install OK with GNOME Packages. When I search for Chromium after the installation with Packages, Software provides no results, but if I click on the desktop outside of Software the result is provided. When I click on All in Software Dropbox and Chromium are not shown as installed. "Install..." is shown instead of the expected "Remove." 2017-08-30 9:50 GMT+02:00 Sebastien Bacher