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---Update--- So I discovered something odd. If I select SDA4 in reffit, I get an error no partition found error described below. If I use PLOP boot manager in the DVD drive and select SDA4 then I get grub loading properly.

So somehow, the MBR that Reffit is using is corrupted. It is using a Hybrid boot loader so this could be the issue that this has gotten messed up somehow by OSX during the resize. Anyone know how to recover this?

Setup: OSX /dev/sda2

Ubuntu /dev/sda4

Reffit is installed and still working. I can select Linux and it was booting to Grub and then I would select Ubuntu and it would boot.

How I caused the problem: Resize OSX partition in disk utility in OSX to free up space for Ubuntu.

Ubuntu is not installed in efi mode as I use custom Nvidia drivers.

I've been able to use grub rescue to boot but using boot-repair tool, leaves me back where I started so something must be wrong somewhere that isn't being found by that tool.

To boot manually from Grub, I use the following commands:

set prefix=(hd0,gpt4)/boot/grub
set root=(hd0,gpt4)
insmod (hd0,gpt4)/boot/grub/i386-pc/linux.mod
linux /vmlinuz root=/dev/sda4 ro
initrd /initrd.img

My grub.cfg file is here:

sudo fdisk -l /dev/sda

WARNING: GPT (GUID Partition Table) detected on '/dev/sda'! The util fdisk doesn't support GPT. Use GNU Parted.

Disk /dev/sda: 250.1 GB, 250059350016 bytes
255 heads, 63 sectors/track, 30401 cylinders, total 488397168 sectors
Units = sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 512 bytes
I/O size (minimum/optimal): 512 bytes / 512 bytes
Disk identifier: 0x00001168

Device Boot      Start         End      Blocks   Id  System
/dev/sda1               1      409639      204819+  ee  GPT
/dev/sda2          409640   377176047   188383204   af  HFS / HFS+
/dev/sda3       377176048   378445583      634768   ab  Darwin boot
/dev/sda4   *   412082176   488392703    38155264   83  Linux

sudo gdisk -l /dev/sda
GPT fdisk (gdisk) version 0.8.5

Partition table scan:
MBR: hybrid
BSD: not present
APM: not present
GPT: present

Found valid GPT with hybrid MBR; using GPT.
Disk /dev/sda: 488397168 sectors, 232.9 GiB
Logical sector size: 512 bytes
Disk identifier (GUID): 000049BC-4A60-0000-F27F-0000207E0000
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 488397134
Partitions will be aligned on 8-sector boundaries
Total free space is 33636933 sectors (16.0 GiB)

Number  Start (sector)    End (sector)  Size       Code  Name
1              40          409639   200.0 MiB   EF00  EFI system partition
2          409640       377176047   179.7 GiB   AF00  Customer
3       377176048       378445583   619.9 MiB   AB00  Recovery HD
4       412082176       488392703   36.4 GiB    EF02  
5       488392704       488396799   2.0 MiB     8200

Any help on how to restore my grub appreciated :)

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up vote 0 down vote accepted

I found the easiest way to deal with the issue was to delete my Ubuntu and reinstall. I tried everything I could think of to restore the hybrid MBR but none of it made any difference.

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