I'm facing this problem too... But I am unable to install the package, look:
--- $ sudo apt install evolution-data-server-online-accounts Reading package lists... Done Building dependency tree Reading state information... Done The following packages were automatically installed and are no longer required: mir-client-platform-mesa4 mir-graphics-drivers-desktop mir-platform-graphics-mesa-kms8 mir-platform-graphics-mesa-x8 mir-platform-input-evdev5 qtubuntu-desktop ubuntu-application-api3-desktop Use 'sudo apt autoremove' to remove them. The following packages will be REMOVED: address-book-service address-book-updater buteo-sync-plugins-contacts-google qtcontact5-galera qtdeclarative5-ubuntu-telephony0.1 unity8 unity8-desktop-session-mir The following NEW packages will be installed: evolution-data-server-online-accounts 0 upgraded, 1 newly installed, 7 to remove and 2 not upgraded. Need to get 33.6 kB of archives. After this operation, 9,486 kB disk space will be freed. Do you want to continue? [Y/n] ^C --- It tries to uninstall Unity8, which I'm experimenting / using now. So, what to do? Thiago -- You received this bug notification because you are a member of Desktop Packages, which is subscribed to evolution in Ubuntu. https://bugs.launchpad.net/bugs/1557612 Title: evolution: e-data-server Error opening directory '/usr/lib/evolution- data-server/credential-modules' Status in evolution package in Ubuntu: Confirmed Bug description: After updating evolution to 3.18.5.1-1ubuntu1 on Ubuntu 16.04, it stopped working: $ evolution (evolution:4688): e-data-server-WARNING **: e_module_load_all_in_directory: Error opening directory '/usr/lib/evolution-data-server/credential-modules': No such file or directory My workaround: sudo apt-get install evolution-data-server-online-accounts Then it worked again. Maybe you need to add "Depends: evolution-data-server-online-accounts (>= 3.18.5)" to evolution package or remove the new depency. To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/evolution/+bug/1557612/+subscriptions -- Mailing list: https://launchpad.net/~desktop-packages Post to : [email protected] Unsubscribe : https://launchpad.net/~desktop-packages More help : https://help.launchpad.net/ListHelp

