bug durante a instalação do sistema, erro ao instalar o grub

[Eduardo Campos]

no final da instalação do sistema xubuntu 16.04 lts, aparece a mensagem dizendo que não foi possivel instalar o grub

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: ubiquity 2.21.51 [modified: lib/partman/automatically_partition/question]
ProcVersionSignature: Ubuntu 4.4.0-15.31-generic 4.4.6
Uname: Linux 4.4.0-15-generic x86_64
ApportVersion: 2.20-0ubuntu3
Architecture: amd64
CasperVersion: 1.368
Date: Fri Mar 25 13:27:53 2016
InstallCmdLine: BOOT_IMAGE=/casper/vmlinuz.efi file=/cdrom/preseed/xubuntu.seed boot=casper quiet splash ---
LiveMediaBuild: Xubuntu 16.04 LTS "Xenial Xerus" - Beta amd64 (20160323)
ProcEnviron:
 LANGUAGE=pt_BR.UTF-8
 PATH=(custom, no user)
 LANG=pt_BR.UTF-8
 SHELL=/bin/bash
SourcePackage: grub-installer
UpgradeStatus: No upgrade log present (probably fresh install)

[Phillip Susi (psusi)]

You are trying to install in EFI mode, but you did not create an EFI system partition. You need to either install in BIOS mode, or create and EFI system partition.