crashes on install from usb pendrive ... error sites faulty dvd media

[Ed Falat]

I received a warning of potential crash after the installer correct handled keyboard identification, but continued anyway and it crashed. Iso checksum was OK.

ProblemType: Bug
DistroRelease: Ubuntu 16.10
Package: ubiquity 16.10.1
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: Fri May 6 19:26:21 2016
InstallCmdLine: file=/cdrom/preseed/ubuntu.seed boot=casper initrd=/casper/initrd.lz quiet splash --- maybe-ubiquity
LiveMediaBuild: Ubuntu 16.10 "Yakkety Yak" - Alpha amd64 (20160506)
ProcEnviron:
 PATH=(custom, no user)
 LANG=en_US.UTF-8
 SHELL=/bin/bash
SourcePackage: ubiquity
UpgradeStatus: No upgrade log present (probably fresh install)

[Phillip Susi (psusi)]

Your installation medium is corrupt. You will need to recreate it and may want to verify it using the check disc option at the boot menu.

[Ed Falat (efalat)]

I had already verified the media, but tried it again with different media and got the same results.
I was using the btrfs option, still got the ubi-console warning and proceded anyway. There was a grub failure.
I was able to chroot into the ssyem by adding the '@' subvolume to the mount instruction.
I had to do a remount of / in chroot to get update-grub to work.
I now have a bootable system and have updated a few times with no ill effects.