the software can't complete the installationo of the system and crashes saying: grub 2 failed or other similar sentences. Then it stops the installation program.g

[stefano]

ubuntu 14. LTS 64 bit
the laptop is a LENOVO G 50-45

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: Wed Jan 13 22:52:54 2016
InstallCmdLine: BOOT_IMAGE=/casper/vmlinuz.efi file=/cdrom/preseed/ubuntu.seed boot=casper only-ubiquity quiet splash --
LiveMediaBuild: Ubuntu 14.04.3 LTS "Trusty Tahr" - Beta amd64 (20150805)
ProcEnviron:
 LANGUAGE=it_IT.UTF-8
 TERM=linux
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=it_IT.UTF-8
SourcePackage: grub-installer
UpgradeStatus: No upgrade log present (probably fresh install)

[Phillip Susi (psusi)]

Your EFI system partition is corrupt; you will need to repair it using dosfsck, or chkdsk/scandisk on Windows.