So, I retested the final images (20160420.1) in both Virtualbox and on my nvidia optimus notebook.
The virtualbox session crashes the install/live session screen (known issue) and threw me into a fully functional plasma session. While kubuntu-desktop is indeed not installed, the installation itself worked fine, and after resetting the system I had no problems booting it. On my notebook (on the intel GPU), the live session experience was exactly the same, but I did no install test. It would be great if someone with such a failed system could try to get a wired network connection, and run 'ubuntu-bug ubiquity' from there and open the bug reporting URL from another system (or write it down). If switching to a TTY doesn't work, The recovery mode from the GRUB "Advanced options from ubuntu" section has an option to drop you to a root shell. That should gather enough logs to tell us why plasma-desktop etc. was missing. If you still cannot file a bug with apport with that, try to at least get the logs from /var/log/installer and /var/log/apt - that can even be done from a Kubuntu 15.10 live session ** Changed in: ubiquity (Ubuntu) Status: Confirmed => Incomplete -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1571564 Title: Unable to install Kubuntu 16.04 To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/kubuntu-meta/+bug/1571564/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs