This solved it for me: http://userbase.kde.org/Akonadi_4.4/Troubleshooting#Environment_Setup -> Titel "Kubuntu 10.4 Upgrade"
citation: Kubuntu 10.4 Upgrade This is a summary of other entries here for those upgrading from Kubuntu 9.10 to 10.4 who may have been using a personal package archive (PPA) for KDE 4.3 for bug fixes. Install missing prerequisites. Remove previous akonadi cache. Start the akonadi service. Install the database. Upgrade the database. Stop and restart the akonadi service. sudo apt-get install virtuoso-server sudo apt-get install mysql-server-5.1 rm -r $HOME/.local/share/akonadi akonadictl start --tlue: open a second terminal mysql_install_db --datadir=$HOME/.local/share/akonadi/db_data/ mysql_upgrade --socket=$HOME/.local/share/akonadi/db_misc/mysql.socket akonadictl stop --tlue: check if the first terminal is ready again/has stopped akonadictl start The mysql_install_db command above will report something like what follows, which you can safely ignore: Installing MySQL system tables... 100501 18:04:30 [Warning] Can't create test file /home/[userid]/.local/share/akonadi/db_data/[hostname].lower-test Reference: forum.kde.org Akonadi 1.2.1 - some issues -- 'akonadictl start' aborts with error after upgrade to 10.4 beta https://bugs.launchpad.net/bugs/554660 You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs