package initramfs-tools 0.136ubuntu6.4 failed to install/upgrade: installed initramfs-tools package post-installation script subprocess returned error exit status 1

[Qazi Hamayun]

When I try to upgrade ubuntu 20.04, after upgrade process I was getting this error

package initramfs-tools 0.136ubuntu6.4 failed to install/upgrade: installed initramfs-tools package post-installation script subprocess returned error exit status 1

ProblemType: Package
DistroRelease: Ubuntu 20.04
Package: initramfs-tools 0.136ubuntu6.4
ProcVersionSignature: Ubuntu 5.8.0-45.51~20.04.1-generic 5.8.18
Uname: Linux 5.8.0-45-generic x86_64
ApportVersion: 2.20.11-0ubuntu27.16
Architecture: amd64
CasperMD5CheckResult: skip
Date: Sun Mar 21 14:27:59 2021
ErrorMessage: installed initramfs-tools package post-installation script subprocess returned error exit status 1
InstallationDate: Installed on 2021-02-24 (25 days ago)
InstallationMedia: Ubuntu 20.04.2.0 LTS "Focal Fossa" - Release amd64 (20210209.1)
PackageArchitecture: all
Python3Details: /usr/bin/python3.8, Python 3.8.5, python3-minimal, 3.8.2-0ubuntu2
PythonDetails: /usr/bin/python2.7, Python 2.7.18, python-is-python2, 2.7.17-4
RelatedPackageVersions:
 dpkg 1.19.7ubuntu3
 apt 2.0.4
SourcePackage: initramfs-tools
Title: package initramfs-tools 0.136ubuntu6.4 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)

[Ubuntu Foundations Team Bug Bot (crichton)]

Thank you for taking the time to report this bug and helping to make Ubuntu better. Reviewing your dmesg attachment in this bug report it seems that there is a problem with your hardware. I recommend performing a back up and then investigating the situation. Measures you might take include checking cable connections and using software tools to investigate the health of your hardware. In the event that is is not in fact an error with your hardware 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.]