package initramfs-tools 0.131ubuntu15 failed to install/upgrade: installed initramfs-tools package post-installation script subprocess returned error exit status 1

[MJ]

Apps crashed/froze for a second for whatever reason, then error appeared,this is not a resident install, my first time running an OS from a USB stick.

ProblemType: Package
DistroRelease: Ubuntu 18.10
Package: initramfs-tools 0.131ubuntu15
ProcVersionSignature: Ubuntu 4.18.0-10.11-generic 4.18.12
Uname: Linux 4.18.0-10-generic x86_64
NonfreeKernelModules: wl
ApportVersion: 2.20.10-0ubuntu13
Architecture: amd64
Date: Mon Feb 4 02:26:33 2019
ErrorMessage: installed initramfs-tools package post-installation script subprocess returned error exit status 1
PackageArchitecture: all
Python3Details: /usr/bin/python3.6, Python 3.6.7rc1, python3-minimal, 3.6.6-1
PythonDetails: N/A
RelatedPackageVersions:
 dpkg 1.19.0.5ubuntu5
 apt 1.7.0
SourcePackage: initramfs-tools
Title: package initramfs-tools 0.131ubuntu15 failed to install/upgrade: installed initramfs-tools package post-installation script subprocess returned error exit status 1
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

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

[Benjamin Drung (bdrung)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. The relevant dpkg terminal log says:

cp: cannot create regular file '/cdrom/casper/initrd.gz.new': No such file or directory