Yeah none of the other solutions in How to install the Pantheon desktop environment? for older versions of Ubuntu worked out. The only ppa that wouldn't say "404 not found" when updated was the ppa:elementary-os/daily, but I couldn't install elementary-desktop, since it just said (in the console) it wouldn't install packages related with it.
The following packages have unmet dependencies:
elementary-desktop : Depends: ubuntu-extras-keyring but it is not installed
Recommends: apport-hooks-elementary but it is not going to be installed
Recommends: bluez-gstreamer but it is not going to be installed
Recommends: elementary-default-settings but it is not going to be installed
Recommends: elementary-os-prerelease but it is not going to be installed
Recommends: fonts-elementary-core but it is not going to be installed
Recommends: gcalctool but it is not going to be installed
Recommends: geary but it is not going to be installed
Recommends: ginn but it is not going to be installed
Recommends: gtksourceview-3.0-theme-solarized-elementary but it is not installed
Recommends: ibus-pinyin
Recommends: light-locker but it is not going to be installed
Recommends: pantheon-greeter but it is not going to be installed
Recommends: plymouth-theme-elementary but it is not going to be installed
Recommends: plymouth-theme-elementary-text but it is not going to be installed
Recommends: print-test-page-elementary but it is not installed
Recommends: pulseaudio-module-gconf but it is not going to be installed
Recommends: switchboard but it is not going to be installed
Recommends: switchboard-gnome-control-center-override but it is not going to be installed
Recommends: switchboard-plug-about but it is not going to be installed
Recommends: switchboard-plug-applications but it is not going to be installed
Recommends: switchboard-plug-datetime but it is not going to be installed
Recommends: switchboard-plug-display but it is not going to be installed
Recommends: switchboard-plug-gcc-bluetooth but it is not going to be installed
Recommends: switchboard-plug-gcc-color but it is not going to be installed
Recommends: switchboard-plug-gcc-mouse but it is not going to be installed
Recommends: switchboard-plug-gcc-network but it is not going to be installed
Recommends: switchboard-plug-gcc-printer but it is not going to be installed
Recommends: switchboard-plug-gcc-sound but it is not going to be installed
Recommends: switchboard-plug-gcc-ua but it is not going to be installed
Recommends: switchboard-plug-gcc-users but it is not going to be installed
Recommends: switchboard-plug-gcc-wacom but it is not going to be installed
Recommends: switchboard-plug-keyboard but it is not going to be installed
Recommends: switchboard-plug-locale but it is not going to be installed
Recommends: switchboard-plug-notifications but it is not installed
Recommends: switchboard-plug-online-accounts but it is not going to be installed
Recommends: switchboard-plug-pantheon-shell but it is not going to be installed
Recommends: switchboard-plug-power but it is not going to be installed
Recommends: switchboard-plug-security-privacy but it is not going to be installed
Recommends: ttf-punjabi-fonts but it is not going to be installed
Recommends: tumbler-plugins-extra but it is not going to be installed
Recommends: user-specific-alternatives but it is not going to be installed
E: Unable to correct problems, you have held broken packages.
Best Answer
I've managed to install elementary desktop by rebuilding ubuntu-extras-keyring locally on my system, like this:
After that,
elementary-desktop
will install, but will error out at the end because it depends onsystemd-shim
which is no longer needed nor wanted with 15.04 having a full SystemD implementation.When it errors out, run
and it should complete the installation.
I expect in the near future the Elementary folks will fix their repository to handle SystemD properly - Ubuntu 15.04 move to SystemD was done a few weeks before the official release and the Elementary guys probably didn't have time to adapt to that.
After installation, you can log out and see "Pantheon" in your display manager's session list, but if you try to log in you'd get just the blueprint paper styled Elementary "beta wallpaper". The problem is that the session starts Slingshot and Gala, but not WingPanel or Plank. Currently I'm using using Slingshot's
ALT-F2
shortcut to open the launcher and run Plank and WingPanel manually (just type the name in all lowercase and hit ENTER).