was trying to install 16.04 along 14.04

[Gopinath Menon]

down loaded iso torrent with Transition. made an USB installer with unetbootin. while installing alongside existing ubuntu 14.04. error msg: ubi-partman failed with exit code 141

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: ubiquity 2.21.63
ProcVersionSignature: Ubuntu 4.4.0-21.37-generic 4.4.6
Uname: Linux 4.4.0-21-generic x86_64
ApportVersion: 2.20.1-0ubuntu2
Architecture: amd64
CasperVersion: 1.376
Date: Wed Jun 22 03:52:44 2016
InstallCmdLine: initrd=/casper/initrd.lz file=/cdrom/preseed/ubuntu.seed boot=casper only-ubiquity quiet splash --- persistent BOOT_IMAGE=/casper/vmlinuz.efi
LiveMediaBuild: Ubuntu 16.04 LTS "Xenial Xerus" - Release amd64 (20160420.1)
ProcEnviron:
 PATH=(custom, no user)
 XDG_RUNTIME_DIR=<set>
 LANG=en_US.UTF-8
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)