Kubuntu 16.04 install crashes setting up encrypted partition

[Nick Andrew]

512 GB SSD already has Windows 8 installed. I shrank the Windows C: partition to 150 GB which left around 350 GB free space.

I had already made a bootable USB drive for Kubuntu with unetbootin. After booting from USB and attempting to use the "Install to hard disk" and selecting manual partitioning, I tried first to create an 8 GB swap partition and then a crypto partition. The installer refused a swap partition outside the crypto partition.

Next I tried to create the crypto partition by itself. When I selected the option I expected the dialog box to extend with passphrase entry fields but it did not. I cannot select "format the partition" nor a mount point, and the installation cannot proceed. Eventually a python error is reported.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: ubiquity 2.21.63
ProcVersionSignature: Ubuntu 4.4.0-21.37-generic 4.4.6
Uname: Linux 4.4.0-21-generic x86_64
ApportVersion: 2.20.1-0ubuntu2
Architecture: amd64
CasperVersion: 1.376
CurrentDesktop: KDE
Date: Sat Jun 4 06:46:00 2016
InstallCmdLine: BOOT_IMAGE=/casper/vmlinuz.efi file=/cdrom/preseed/kubuntu.seed boot=casper maybe-ubiquity quiet splash ---
LiveMediaBuild: Kubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)

[Ubuntu Foundations Team Bug Bot (crichton)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. Reviewing your log files attached to this bug report it seems that there is a problem with your installation media (CD/DVD). You can verify the integrity of the Ubuntu ISO files you downloaded by following the instructions at https://help.ubuntu.com/community/HowToMD5SUM. You might also retry your installation with new media. In the event that is is not in fact an error with your installation media please set the bug's status back to New. Thanks and good luck!

[This is an automated message. I apologize if it reached you inappropriately; please just reply to this message indicating so.]

[Nick Andrew (nick-nick-andrew)]

71f29e721708bb743ee646a820994fc0 /mnt/ubuntu-iso/kubuntu-16.04-desktop-amd64.iso OKAY

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[GizmoChicken (gizmochicken)]

This bug report seems to include at least TWO distinct bugs.

1. "The installer refused a swap partition outside the crypto partition" seems related to Bug #1490824 which affects all flavors Ubuntu. A simple workaround for this bug (on most flavors) is to NOT create a swap file during installation, but instead to create an extra encrypted volume during installation, format it with most any file format other than swap, and then, after installation is complete, format the extra encrypted volume as swap, followed by making appropriate changes to fstab, etc.

2. "When I selected the option I expected the dialog box to extend with passphrase entry fields but it did not" seems related to Bug #1510731 which ONLY affects Kubuntu (and KDE neon and Lubuntu Next (LXQt), which use the KDE variant of Ubiquity).