Comment 67 for bug 1265192

This is a horrible bug. I spent the last 2 days testing & reproducing it. I want to share my findings with you.

I was not hit by the bug on "real metal" install as I always go the [Something else] partitioning route when installing - I never trust any OS installer to play with my partitions, I partition separately and install inside already created partitions (I usually allow formatting of root partition as not doing this will make some installers complain or even worse, trigger a different set of bugs). I found out about this wipe out bug while reading on the net and I couldn't believe something like this is really possible - so I had to see it with my own eyes.

For testing purposes I've used VM environments - namely VMware Player and Virtual Box.

In VMware Player I've tested using BIOS/MBR HDD formatting as well as EFI/GPT HDD formatting. In Virtual Box I've only tested using BIOS/MBR HDD formatting. BIOS/MBR versus EFI/GPT (or the VM environment) made no difference.

For all above scenarios I've tested using Windows 7 and Windows 8.1. Both were obtained as ISOs from Microsoft's TechNet (Free Enterprise Evaluation versions). Well, this made the difference.

While I've read that a number of people wiped out Windows 7 as well, in all my tests Windows 7 was not wiped.
However, in all my tests, Windows 8 was wiped out every time.

Test scenario:
 A. Common part, working just fine for both Windows 7 and Windows 8:
  1. VM HDD is 30GB;
  2. Install Windows (7/8) in a 20GB partition created at install time - so leave 10GB free for installing Linux later;
  3. After Windows (7/8) finishes installing and boots OK, shut down the VM.
  4. Install Linux - any *buntu 14.04.1 - on the free 10GB. I used a custom (built by myself) i386 LXDE version based on 14.04.1 for BIOS/MBR. For EFI/GPT I've used the official Ubuntu 14.04.1 amd64 ISO. Do the installation going the [Something else] route and creating a Linux partition in the 10GB of free space.
  5. After Linux finishes installing and boots OK, shut down the VM.
 B. Now it's time to see the bug in action. For this purpose we'll re-install Linux:
  I. Windows 7 VM:
   - start the VM with the same ISO used at step 4.
   - when the installer gets at the [Installation type] stage, read top line: "This computer currently has Windows 7 and Ubuntu 14.04.1 LTS on it.". Ubuntu recognizes the presence of Windows 7 - please see attachment.
   - choose [Erase Ubuntu 14.04.1 LTS and reinstall]. Notice how this is the 1st option in the list, the 2nd being [Erase everything and reinstall] which mentions something about deleting both Windows 7 and Ubuntu. Notice how the [Encrypt ...] and [Use LVM ...] options are INACTIVE.
   - finish re-installing;
   - check partitions - Windows 7 is still there;
   - reboot and see that Windows 7 also appears in GRUB and still works fine when started;
   - reboot and see that Linux also works fine when started.
  II. Windows 8 VM:
   - start the VM with the same ISO used at step 4.
   - when the installer gets at the [Installation type] stage, read top line: "This computer currently has Ubuntu 14.04.1 LTS on it.". Ubuntu DOESN'T recognize the presence of Windows 8 - please see attachment.
   - choose [Erase Ubuntu 14.04.1 LTS and reinstall]. Notice how this time this is the 2nd option in the list, the 1st being [Install ... alongside Ubuntu 14.04.1 LTS]. Notice how the [Encrypt ...] and [Use LVM ...] options are ACTIVE this time. With Windows 8 not being recognized, this option is actually option [Erase everything and reinstall] from Windows 7 VM scenario. After all, if there's no Windows 8 (detected), then Ubuntu 14.04.1 LTS = everything. Also, one should select 2nd option ([Erase everything and reinstall]) at I. in order for [Encrypt ...] and [Use LVM ...] to become active.
   - finish re-installing;
   - check partitions - Windows 8 is gone;
   - reboot and see that Windows 8 no longer appears in GRUB (GRUB menu doesn't even show up any more);
   - Linux took over the full HDD (but works fine).

So, finally, the problem seems to be the fact that the Ubuntu installer(?) is not able to detect Windows 8 presence which makes [Erase Ubuntu 14.04.1 LTS and reinstall] = [Erase everything and reinstall] in Windows 8 scenario.

In Windows 7 scenario, as Ubuntu installer(?) detects Windows 7 presence, [Erase Ubuntu 14.04.1 LTS and reinstall] means "keep anything else and only reinstall Ubuntu 14.04.1".

That's all folks!