i just downloaded new ubuntu 18 from mirror of utah.edu and written that image of usb stick through ubuntu app startup disk and then, just went on install with removing ubuntu 16 and installing 18 by erasing it. it asked for downloading while install and i accepted. Now all of sudden showing me this important grub-installer package not found in iso. seems funny and resulted critical situation for not having any operating system with me to download and re-install

[hari]

i just downloaded new ubuntu 18 from mirror of utah.edu and written that image of usb stick through ubuntu app startup disk and then, just went on install with removing ubuntu 16 and installing 18 by erasing it. it asked for downloading while install and i accepted. Now all of sudden showing me this important grub-installer package not found in iso. seems funny and resulted critical situation for not having any operating system with me to download and re-install

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: ubiquity 18.04.14
ProcVersionSignature: Ubuntu 4.15.0-20.21-generic 4.15.17
Uname: Linux 4.15.0-20-generic x86_64
ApportVersion: 2.20.9-0ubuntu7
Architecture: amd64
CasperVersion: 1.394
CurrentDesktop: ubuntu:GNOME
Date: Sun Jun 10 21:19:59 2018
InstallCmdLine: BOOT_IMAGE=/casper/vmlinuz file=/cdrom/preseed/ubuntu.seed boot=casper only-ubiquity quiet splash ---
LiveMediaBuild: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180426)
ProcEnviron:
 LANGUAGE=en_US.UTF-8
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
 LC_NUMERIC=C.UTF-8
SourcePackage: grub-installer
UpgradeStatus: No upgrade log present (probably fresh install)

[Phillip Susi (psusi)]

Your installation medium is corrupt; you will need to recreate it and may want to verify it using the check disc option at the boot menu.