View Full Version : Unable to boot to Windows 7 after 12.10 upgrade

December 30th, 2012, 12:34 AM
Hi everyone,

I recently upgraded to 12.10 and can no longer boot into Windows 7. When I select the Windows 7 partition in grub I get "error: device format "ldm... invlaid: must be (f|h)dN, with 0<= N < 128" (... is a bunch of numbers and characters) then I press any key and get "a disk read error occured, press ctrl+alt+del to restart". I have done a little research and this bug seems to be similar to mine https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1061255

I have Ubuntu 12.04 on a usb that I can boot into for boot repair ("Workaround 3" in the above post), I just want to make sure that other people think that is a good idea, because I am fairly new to Ubuntu/grub. Thanks for any advice!

December 30th, 2012, 12:47 AM
Welcome to the forums.

Post the link to the BootInfo report that this creates. Is part of Boot-Repair:

Boot Repair -Also handles LVM, GPT, separate /boot and UEFI dual boot.:
You can repair many boot issues with this or 'Create BootInfo' report (Other Options) & post the link it creates, so we can see your exact configuration and diagnose advanced problems.
Install in Ubuntu liveCD or USB or Full RepairCD with Boot-Repair (for newer computers)

December 30th, 2012, 01:17 AM
Thanks for the quick response.


December 30th, 2012, 02:11 AM
Did you convert Windows back from UEFI to BIOS? It is unusual to have the vendor repair partition to have efi files and be sda5.

Also you grub also is a bit unusual in that it is directly looking for core.img in the partition. Normally that is in the sectors after the MBR and before first partition. I would use Boot-Repair to update grub.

Windows looks like it has all its boot files, but NTFS partitions are real sensitive to any changes. They have to have the PBR - partition boot sector have correct info. Boot script generally says it is ok, but it does not check all the details. You may need to run chkdsk from a Windows repairCD or make other repairs from the Windows repairCD.
Make your own Windows repairCD (not vendor recovery):

How to Boot to the System Recovery Options in Windows 7

December 30th, 2012, 02:46 AM
Thanks so much for the help, oldfred!

I ran boot repair, and I am now able to boot into my Windows 7 partition.

December 30th, 2012, 05:43 AM
It must have been related to how grub was loading. I was sure that it was something in Windows. :)

Glad you got it working.