package grub-pc 2.04-1ubuntu26.4 failed to install/upgrade: installed grub-pc package post-installation script subprocess returned error exit status 1

[Brian Neal]

Error occurred on do-release-upgrade from 18.04 LTS in AWS EC2.

ProblemType: Package
DistroRelease: Ubuntu 20.04
Package: grub-pc 2.04-1ubuntu26.4
ProcVersionSignature: Ubuntu 5.4.0-1025.25~18.04.1-aws 5.4.60
Uname: Linux 5.4.0-1025-aws x86_64
ApportVersion: 2.20.11-0ubuntu27.9
Architecture: amd64
CasperMD5CheckResult: skip
Date: Wed Sep 30 06:12:32 2020
DuplicateSignature:
 package:grub-pc:2.04-1ubuntu26.4
 Setting up grub-pc (2.04-1ubuntu26.4) ...
 dpkg: error processing package grub-pc (--configure):
  installed grub-pc package post-installation script subprocess returned error exit status 1
Ec2AMI: ami-03ba3948f6c37a4b0
Ec2AMIManifest: (unknown)
Ec2AvailabilityZone: us-west-1a
Ec2InstanceType: m5.large
Ec2Kernel: unavailable
Ec2Ramdisk: unavailable
ErrorMessage: installed grub-pc package post-installation script subprocess returned error exit status 1
ProcCmdLine: BOOT_IMAGE=/boot/vmlinuz-5.4.0-1025-aws root=UUID=c03b791b-60ef-4ae1-82b5-5c9ab6b4d08f ro console=tty1 console=ttyS0 nvme_core.io_timeout=4294967295
Python3Details: /usr/bin/python3.8, Python 3.8.2, python3-minimal, 3.8.2-0ubuntu2
PythonDetails: /usr/bin/python2.7, Python 2.7.18rc1, python-is-python2, 2.7.17-4
RelatedPackageVersions:
 dpkg 1.19.7ubuntu3
 apt 2.0.2ubuntu0.1
SourcePackage: grub2
Title: package grub-pc 2.04-1ubuntu26.4 failed to install/upgrade: installed grub-pc package post-installation script subprocess returned error exit status 1
UpgradeStatus: Upgraded to focal on 2020-09-30 (0 days ago)

[Launchpad Janitor (janitor)]

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