Why does kickstart installation of Red Hat Enterprise Linux 7.1 fail with an error "An unknown error has occurred" but 7.0 works just fine?

Issue

• Why does kickstart installation of Red Hat Enterprise Linux 7.1 fail with an error An unknown error has occurred but 7.0 works just fine?
• The kickstart file used for installation on VMWare Virtual Machines is as follows.

cdrom
lang en_US.UTF-8
keyboard 'us'
rootpw  redhat
firewall --disabled
services --disabled=NetworkManager
authconfig --enableshadow --passalgo=sha512
selinux --disabled
firstboot --disabled
timezone --utc Europe/Moscow
user --name=administrator --groups=wheel --homedir=/home/administrator --shell=/bin/bash --password=123456 --plaintext
graphical
services --disabled NetworkManager
%packages
@base
@core
@legacy-unix
@network-tools
@performance
@system-admin-tools
%end