Install CUBUNTU 16.04 sur ASUX X555L - grub-efi-amd64-signed - target grub error

[zorganix]

Installation in EFI mode ends with this error message:

Le paquet grub-efi-amd64-signed n'a pas pu être installé dans /target/. En l'absence du programme de démarrage GRUB, le système installé ne pourra pas démarrer. (grub-efi-amd64-signed could not be installed in /target/. Without GRUB boot program installed system will not be able to start.)

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: ubiquity 2.21.43 [modified: usr/share/ubiquity/apt-setup]
ProcVersionSignature: Ubuntu 4.4.0-2.16-generic 4.4.0
Uname: Linux 4.4.0-2-generic x86_64
NonfreeKernelModules: nvidia_modeset nvidia
ApportVersion: 2.19.4-0ubuntu2
Architecture: amd64
CasperVersion: 1.366
Date: Sat Feb 13 22:44:03 2016
LiveMediaBuild: cubuntu 16.04 208 ALL - Release amd64
SourcePackage: ubiquity
UbiquitySyslog:

UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

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

[Seal20 (swiller)]

This occurs to me whenever the number of the partition choice, I had no pb with the other distros (Xubuntu 16.04, Ubuntu 16.04, Gnome 16, Mate and Cinamon)
This is a Cubuntu bug.