The problem was the Windows flash drive. I zeroed it out, and then
installation finished fine. I wanted the flash drive to be the boot drive,
but the installer skipped it, and used the larger drive for all partitions.
The system has been fine ever since.

On Mon, Jan 9, 2017, 9:15 PM Christopher Michael Rogers <
<email address hidden>> wrote:

> I was able to use a boot repair tool while booted from the installer
> USB:
>
> http://askubuntu.com/questions/226061/how-to-install-the-boot-repair-
> tool-in-an-ubuntu-live-disc
> <http://askubuntu.com/questions/226061/how-to-install-the-boot-repair-tool-in-an-ubuntu-live-disc>
>
> That seemed to fix things. Sorry for the delayed response.
>
> On Mon, Jan 9, 2017, 8:05 PM Mathieu Trudel-Lapierre <<email address hidden>
> >
> wrote:
>
> > This most likely has nothing at all to do with Fastboot or Secure Boot.
> > The system appears to be correctly detected as booted in UEFI mode;
> > which will trigger grub-installer removing grub-pc (since it's not
> > needed).
> >
> > For instance, from the logs:
> > Nov  4 22:31:02 lubuntu grub-installer: info: architecture: amd64/efi
> >
> > Can you successfully install using the alternate ISO? It seems to me
> > like that one should work, and we're likely seeing the effect of bug
> > 1649462 (so Phillip would be right that this is an issue with how
> > Lubuntu is "packaged").
> >
> > I'll run the test here to make sure. This shows we don't have enough
> > people testing ISOs in UEFI mode.
> >
> > --
> > You received this bug notification because you are subscribed to a
> > duplicate bug report (1643354).
> > https://bugs.launchpad.net/bugs/1639374
> >
> > Title:
> >   grub-pc fails to remove, causing lubuntu installs to crash
> >
> > Status in grub2 package in Ubuntu:
> >   Triaged
> >
> > Bug description:
> >   Crashed during install
> >
> >   ProblemType: Bug
> >   DistroRelease: Ubuntu 16.10
> >   Package: ubiquity 16.10.14
> >   ProcVersionSignature: Ubuntu 4.8.0-22.24-generic 4.8.0
> >   Uname: Linux 4.8.0-22-generic x86_64
> >   ApportVersion: 2.20.3-0ubuntu8
> >   Architecture: amd64
> >   CasperVersion: 1.379
> >   Date: Fri Nov  4 18:31:30 2016
> >   InstallCmdLine: BOOT_IMAGE=/casper/vmlinuz.efi
> > file=/cdrom/preseed/lubuntu.seed cdrom-detect/try-usb=true persistent
> > noprompt floppy.allowed_drive_mask=0 ignore_uuid boot=casper
> only-ubiquity
> > quiet splash ---
> >   LiveMediaBuild: Lubuntu 16.10 "Yakkety Yak" - Release amd64
> (20161012.1)
> >   ProcEnviron:
> >    PATH=(custom, no user)
> >    XDG_RUNTIME_DIR=<set>
> >    LANG=en_US.UTF-8
> >    LC_NUMERIC=C.UTF-8
> >   SourcePackage: grub-installer
> >   UpgradeStatus: No upgrade log present (probably fresh install)
> >
> > To manage notifications about this bug go to:
> >
> https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1639374/+subscriptions
> >
>
> --
> You received this bug notification because you are subscribed to a
> duplicate bug report (1649975).
> https://bugs.launchpad.net/bugs/1639374
>
> Title:
>   grub-pc fails to remove, causing lubuntu installs to crash
>
> Status in grub2 package in Ubuntu:
>   Triaged
>
> Bug description:
>   Crashed during install
>
>   ProblemType: Bug
>   DistroRelease: Ubuntu 16.10
>   Package: ubiquity 16.10.14
>   ProcVersionSignature: Ubuntu 4.8.0-22.24-generic 4.8.0
>   Uname: Linux 4.8.0-22-generic x86_64
>   ApportVersion: 2.20.3-0ubuntu8
>   Architecture: amd64
>   CasperVersion: 1.379
>   Date: Fri Nov  4 18:31:30 2016
>   InstallCmdLine: BOOT_IMAGE=/casper/vmlinuz.efi
> file=/cdrom/preseed/lubuntu.seed cdrom-detect/try-usb=true persistent
> noprompt floppy.allowed_drive_mask=0 ignore_uuid boot=casper only-ubiquity
> quiet splash ---
>   LiveMediaBuild: Lubuntu 16.10 "Yakkety Yak" - Release amd64 (20161012.1)
>   ProcEnviron:
>    PATH=(custom, no user)
>    XDG_RUNTIME_DIR=<set>
>    LANG=en_US.UTF-8
>    LC_NUMERIC=C.UTF-8
>   SourcePackage: grub-installer
>   UpgradeStatus: No upgrade log present (probably fresh install)
>
> To manage notifications about this bug go to:
> https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1639374/+subscriptions
>