Thank you for taking the time to report this bug and helping to make Ubuntu better. The version of update-initramfs that you likely have installed is unable to work on a persistent usb stick. You can resolve this issue by upgrading the version of casper on your system. This can be done via the commands:
sudo apt-get update; sudo apt-get install casper Then performing the software update or installation that you were originally trying. If this does not resolve your bug please set its status back to New. Thanks in advance! ** Tags added: needs-new-casper ** Changed in: initramfs-tools (Ubuntu) Status: New => Invalid -- You received this bug notification because you are a member of Ubuntu Touch seeded packages, which is subscribed to initramfs-tools in Ubuntu. https://bugs.launchpad.net/bugs/1614223 Title: package initramfs-tools 0.122ubuntu8 failed to install/upgrade: subprocess installed post-installation script returned error exit status 1 Status in initramfs-tools package in Ubuntu: Invalid Bug description: Only updating a new instalation of Ubuntu ProblemType: Package DistroRelease: Ubuntu 16.04 Package: initramfs-tools 0.122ubuntu8 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 Date: Wed Aug 17 18:54:42 2016 ErrorMessage: subprocess installed post-installation script returned error exit status 1 LiveMediaBuild: It PackageArchitecture: all RelatedPackageVersions: dpkg 1.18.4ubuntu1 apt 1.2.10ubuntu1 SourcePackage: initramfs-tools Title: package initramfs-tools 0.122ubuntu8 failed to install/upgrade: subprocess installed post-installation script returned error exit status 1 UpgradeStatus: No upgrade log present (probably fresh install) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/initramfs-tools/+bug/1614223/+subscriptions -- Mailing list: https://launchpad.net/~touch-packages Post to : touch-packages@lists.launchpad.net Unsubscribe : https://launchpad.net/~touch-packages More help : https://help.launchpad.net/ListHelp