Grub2 failed t install over previously installed instance.

[Alan Searchwell]

I was doing an OEM install in preparation to sell this laptop and the grub2 part of the installation failed with an error "grub installation failed grub-efi-amd64-signed package failed to install into /target/." Booting to a live session from the thumb drive, deleting the "ubuntu"folder from the EFI folder in the EFI partition and doing a regular install worked fine. Trying to do the OEM install over the regular install failed again.

ProblemType: Bug
DistroRelease: Ubuntu 18.04
Package: ubiquity 18.04.14.14 [modified: lib/partman/automatically_partition/question]
ProcVersionSignature: Ubuntu 5.3.0-28.30~18.04.1-generic 5.3.13
Uname: Linux 5.3.0-28-generic x86_64
ApportVersion: 2.20.9-0ubuntu7.9
Architecture: amd64
CasperVersion: 1.394.3
CurrentDesktop: ubuntu:GNOME
Date: Tue Oct 11 23:38:53 2022
InstallCmdLine: BOOT_IMAGE=/casper/vmlinuz file=/cdrom/preseed/ubuntu.seed boot=casper only-ubiquity quiet splash oem-config/enable=true ---
LiveMediaBuild: Ubuntu 18.04.4 LTS "Bionic Beaver" - Release amd64 (20200203.1)
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)