Error trying to install ubuntu side by side with windows 8.1 in efi mode. Installer crashes after signaling an error in installing grub-efi-amd64-signed

[Francesco Corucci]

Hello,

I'm trying to install Ubuntu in dual boot with a pre-exhisting windows 8.1 system in EFI mode.
I've resized the main windows partition leaving free space, then tried to install ubuntu.

Among the installing options I selected "others" to manually specify the partitioning of my disk.
Created a swap partition and another one for "/", leaving the rest untouched.
Just specified /media/windows mount point for my main ntfs partition.

The installer works for a while, then raises an error while grub-efi-amd64-signed. It then crashes, with a bug report mentioning package ubiquity 2.18.8.9.

Tried again, this time the installer notices that the computer currently has a windows boot manager and ubuntu 14.04.3 LTS on it. Tried by selecting "erase ubuntu and reinstall", without success.

I am installing from a USB stick.
Boot is not in secure mode.

Can you please help me?

Thanks

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: ubiquity 2.18.8.9 [modified: lib/partman/automatically_partition/question]
ProcVersionSignature: Ubuntu 3.19.0-25.26~14.04.1-generic 3.19.8-ckt2
Uname: Linux 3.19.0-25-generic x86_64
ApportVersion: 2.14.1-0ubuntu3.11
Architecture: amd64
CasperVersion: 1.340.2
Date: Mon Sep 21 00:39:09 2015
InstallCmdLine: BOOT_IMAGE=/casper/vmlinuz.efi file=/cdrom/preseed/ubuntu.seed cdrom-detect/try-usb=true noprompt floppy.allowed_drive_mask=0 ignore_uuid boot=casper only-ubiquity quiet splash --
LiveMediaBuild: Ubuntu 14.04.3 LTS "Trusty Tahr" - Beta amd64 (20150805)
ProcEnviron:
 TERM=linux
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
SourcePackage: grub-installer
UpgradeStatus: No upgrade log present (probably fresh install)

[Malte Hellmeier (f-iefo-i)]

Same problem here!
https://bugs.launchpad.net/ubuntu/+source/grub-installer/+bug/1498049

[Launchpad Janitor (janitor)]

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