crash at the end of installation, grub install

[Wolfgang Hene]

/var/log/syslog
/var/log/partman

ProblemType: Bug
DistroRelease: Ubuntu 14.04
Package: ubiquity 2.18.8 [modified: usr/share/ubiquity/apt-setup]
ProcVersionSignature: Ubuntu 3.13.0-24.47-generic 3.13.9
Uname: Linux 3.13.0-24-generic x86_64
ApportVersion: 2.14.1-0ubuntu3
Architecture: amd64
CasperVersion: 1.340
Date: Tue Jun 14 11:22:10 2016
LiveMediaBuild: mintyMac 14.04 - Release amd64
ProcEnviron:
 LANGUAGE=de_DE.UTF-8
 PATH=(hostname, no user)
 LANG=de_DE.UTF-8
 SHELL=/bin/bash
SourcePackage: ubiquity
UbiquitySyslog:

UpgradeStatus: No upgrade log present (probably fresh install)