package initramfs-tools 0.125ubuntu3 failed to install/upgrade: subprocess installed post-installation script returned error exit status 1

[me]

Plugged a Logitech wireless mouse dongle into a USB3 port

ProblemType: Package
DistroRelease: Ubuntu 16.10
Package: initramfs-tools 0.125ubuntu3
ProcVersionSignature: Ubuntu 4.8.0-14.15-generic 4.8.0-rc7
Uname: Linux 4.8.0-14-generic x86_64
ApportVersion: 2.20.3-0ubuntu7
AptOrdering: NULL: ConfigurePending
Architecture: amd64
Date: Wed Oct 5 19:27:14 2016
DpkgTerminalLog:
 Setting up initramfs-tools (0.125ubuntu3) ...
 sudoupdate-initramfs: deferring update (trigger activated)
 cp: cannot create regular file '/cdrom/casper/initrd.gz.new': No such file or directory
 dpkg: error processing package initramfs-tools (--configure):
  subprocess installed post-installation script returned error exit status 1
ErrorMessage: subprocess installed post-installation script returned error exit status 1
PackageArchitecture: all
RelatedPackageVersions:
 dpkg 1.18.10ubuntu1
 apt 1.3~rc4ubuntu1
SourcePackage: initramfs-tools
Title: package initramfs-tools 0.125ubuntu3 failed to install/upgrade: subprocess installed post-installation script 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.

[Miles Marx (k-vp)]

This just occurred for me after using tasksel to switch from Ubuntu Mate to Xubuntu. I simply deselected one, waited for the process to finish, then reinstalled and re-ran tasksel. I did get an intitramfs related error when reinstalling tassel, but I ignored it and continued to install Xubuntu. Xubuntu seemed to install successfully with no errors, and I am currently using it to type this note.

The error occurred immediately after logging into the new Xubuntu installation. I know nothing else.

Cheers!