Ubuntu 20.04 installation failure

[Gary Hutchin]

I am attempting to install Ubuntu 20.04 on a VM using Virtualbox. Everything seems fine until what appears to be the final stage, copying files, after entering my name, the name of the machine and setting up a password etc.

I have tried adding the ISO from a location on my Win10 boot drive, and also a USB3 storage device, but get the exact same error.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: ubiquity 20.04.15
ProcVersionSignature: Ubuntu 5.4.0-26.30-generic 5.4.30
Uname: Linux 5.4.0-26-generic x86_64
NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair
ApportVersion: 2.20.11-0ubuntu27
Architecture: amd64
CasperMD5CheckResult: pass
CasperVersion: 1.445
CurrentDesktop: ubuntu:GNOME
Date: Wed Apr 29 08:53:17 2020
InstallCmdLine: file=/cdrom/preseed/ubuntu.seed initrd=/casper/initrd quiet splash --- maybe-ubiquity
LiveMediaBuild: Ubuntu 20.04 LTS "Focal Fossa" - Release amd64 (20200423)
ProcEnviron:
 LANGUAGE=en_GB.UTF-8
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_GB.UTF-8
 LC_NUMERIC=C.UTF-8
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)