Installation Failing on the last step i.e grub-install failing

[Praneeth Chokka]

i tried to dual boot ubuntu with windows 10, with a home partition. The only problem which I've faced was the installer crashing on running the grub-install and it always exits the installer with the error message fatal error: failed to install grub ( something along these lines ) on /dev/sdxy.

Here xy represent the partion that I am trying to install it on. I've tried to install it on many different things. I've tried to install it with the windows bootloader thing as it is by default. which fails. Then I tried to make an efi partition on the hardisk and then install the boot loader there but it still fails.

The installer always just displays the error message and the entire live boot hangs up. Like Ctrl + Alt + T doesn't open anything nor does clicking on stuff. Even trying to close the presently open windows fails. This is like the only time that the entire live boot didn't hang and here I am typing this.

Also I tried to run the grub-install / update grub2 command on the cli live boot but it says failed to obtain canonical path of /cow ( something along these liines ). I tried umount /cow but still the same message.

When I try to boot into this after the installer hangs up by just forecfully restarting all I get is the grub cli.

Edit: I still don't know what the problem is but i did manage to install 20.04 by upgrading from 18.04.

ProblemType: Bug
DistroRelease: Ubuntu 20.04
Package: ubiquity 20.04.15
ProcVersionSignature: Ubuntu 5.4.0-26.30-generic 5.4.30
Uname: Linux 5.4.0-26-generic x86_64
NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair
ApportVersion: 2.20.11-0ubuntu27
Architecture: amd64
CasperMD5CheckMismatches: ./pool/restricted/n/nvidia-graphics-drivers-390/nvidia-utils-390_390.132-0ubuntu2_amd64.deb
CasperMD5CheckResult: skip
CasperVersion: 1.445
CurrentDesktop: ubuntu:GNOME
Date: Sat May 2 15:38:25 2020
InstallCmdLine: BOOT_IMAGE=/casper/vmlinuz file=/cdrom/preseed/ubuntu.seed maybe-ubiquity quiet splash acpi=off ---
LiveMediaBuild: Ubuntu 20.04 LTS "Focal Fossa" - Release amd64 (20200423)
ProcEnviron:
 LANGUAGE=en_IN
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_IN
 LC_NUMERIC=C.UTF-8
SourcePackage: grub-installer
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

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