package grub-efi-amd64 2.02-2ubuntu8.2 failed to install/upgrade: installed grub-efi-amd64 package post-installation script subprocess returned error exit status 1

[hardeepdadiala]

while upgrading to Ubantu 18.04 version pc hanged and it did not orked even after leaving for hours

ProblemType: Package
DistroRelease: Ubuntu 18.04
Package: grub-efi-amd64 2.02-2ubuntu8.2
ProcVersionSignature: Ubuntu 4.4.0-131.157-generic 4.4.134
Uname: Linux 4.4.0-131-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.2
Architecture: amd64
Date: Sat Aug 11 22:33:39 2018
DistributionChannelDescriptor:
 # This is a distribution channel descriptor
 # For more information see http://wiki.ubuntu.com/DistributionChannelDescriptor
 canonical-oem-somerville-xenial-amd64-20160624-2
ErrorMessage: installed grub-efi-amd64 package post-installation script subprocess returned error exit status 1
InstallationDate: Installed on 2018-04-30 (103 days ago)
InstallationMedia: Ubuntu 16.04 "Xenial" - Build amd64 LIVE Binary 20160624-10:47
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-4.4.0-131-generic.efi.signed root=UUID=51e2afee-e9ee-4527-adf4-853e7c5827d5 ro acpi_rev_override quiet splash vt.handoff=7
Python3Details: /usr/bin/python3.6, Python 3.6.5, python3-minimal, 3.6.5-3ubuntu1
PythonDetails: /usr/bin/python2.7, Python 2.7.15rc1, python-minimal, 2.7.15~rc1-1
RelatedPackageVersions:
 dpkg 1.19.0.5ubuntu2
 apt 1.6.3
SourcePackage: grub2
Title: package grub-efi-amd64 2.02-2ubuntu8.2 failed to install/upgrade: installed grub-efi-amd64 package post-installation script subprocess returned error exit status 1
UpgradeStatus: Upgraded to bionic on 2018-08-11 (0 days ago)

[Phillip Susi (psusi)]

It looks like grub tried to ask a question and debconf ran the gtk frontend and somehow dropped you to a subshell, which you typed exit from, then the gtk frontend errored out, causing the grub script to return the error.