Hi I am on Ubuntu 16.04. When running sudo apt-get upgrade I obtain The following packages will be upgraded: akregator-trinity amarok-common Etc all together some 66 packages Then saying yes WARNING: The following packages cannot be authenticated! Then even saying yes I obtain Err:11 http://mirror.ppa.trinitydesktop.org/trinity/deb/trinity-sb xenial/main-r14 amd64 kate-trinity amd64 4:14.0.10~pre13-0ubuntu16.04.0+1 404 Not Found Can somebody please tell me what is wrong here? Thanks and regards Uwe Brauer