Yet Another Helping The Next Guy
I bought my son a shiny new Ivy Bridge based Asus laptop from dealnews for high school graduation. Of course, he only runs Ubuntu, but I wanted to keep the Win 7 64 around for flashing BIOS and related reasons (and someday he may need to run some Windows program....)
It's pretty straight-forward to install Ubuntu alongside windows in a dual-boot fashion as the Live installer knows how to do this. But apparently not on some UEFI based systems--or that's what I thought. It turns out, the installer knows how to work with UEFI systems as well. It just doesn't know how to do it on a system with a broken/corrupt/obscured GUID Partition Table (gpt).
I've used gpt for years as I used to work in HP's Itanium Linux lab. And I've seen some GPT tables corrupted before. The ASUS (at least this one) ships with the secondary GPT corrupted. The last partition (I think 5th) somehow extends INTO the secondary GPT. (Think of the secondary as a backup table in case the primary gets corrupted--a failsafe.) This corrupt secondary table makes the partition table unreadable or possibly unusable to Ubuntu (and moreover, to the underlying libparted and the parted utility.) The installer just "determined" that the disk was unformatted so it kindly offered to just install Ubuntu to this blank disk (destroying all the existing partitions in the process.) Not so good.
I downloaded gdisk (from Universe) as it seems to be designed from the ground up for GPT tables and it was able to read the partition table and show me the partitions. These matched up with what /proc/partitions was showing me (which seemed to be right all along.) It also matched up with what I was seeing in Windows 7. ASUS ships with a C drive, a D drive, and a recovery drive along with the normal EFI system partition (ESP) and a Microsoft Reserved Partition (MSR). So the layout looked something like this:
Number Start (sector) End (sector) Size Code Name
1 2048 411647 200.0 MiB EF00 EFI system partition
2 411648 673791 128.0 MiB 0C01 Microsoft reserved part
3 673792 339511295 161.6 GiB 0700 Basic data partition
4 339511296 925575167 279.5 GiB 0700 Basic data partition
5 925575168 976773167 24.4 GiB 2700 Basic data partition
Where 3 is C (OS) drive, 4 is D (DATA) drive, and 5 is the ASUS Recovery partition. It is partition 5 that seemed to be the source of the error:
Warning! Secondary partition table overlaps the last partition by
You will need to delete this partition or resize it in another utility.