Ubuntu – Grub and Ubuntu disappeared after Windows update


I had Windows 10 and Ubuntu 14.04 installed in dual boot.
Roughly 125GB each.

After the Windows update the PC only showed me the grub rescue terminal. I could neither use Ubuntu nor use Windows.

I inserted the liveCD and ran boot-repair.

After that Windows appeared normally, but no GRUB and no Ubuntu.

This is what I get when I run sudo fdisk -l:

enter image description here

Ubuntu must be either /dev/sda2 or /dev/sda4, since they are the biggest partitions, but neither of them is recognized as a Linux system.

What should I do?

Best Answer

Windows 10 Anniversary Update, and I understand that Windows 10 Creators Update is the same, both can delete Linux partitions for no particular reason. It's not fully understood what factors trigger this action, however it might be related to MBR formatted disks.

Your sda4 is an extended partition that currently contains sda5 swap partition, and also held the previous Ubuntu partition, presumably sda6... which was located between blocks 253681662 and 484151295.

You can try using testdisk to recover your partition.

Boot to a Ubuntu Live DVD/USB, and in the terminal type:

sudo apt-get update

sudo apt-get install testdisk

sudo testdisk

See http://www.cgsecurity.org/wiki/TestDisk_Step_By_Step for help on how to use this tool.