I've attempted to install 9.04 on an older toshiba laptop with a new 300GB drive and am getting the dreaded Grub error 18 that indicates that grub is looking beyond the bios readable area of the HD and failing.

I just let ubuntu roll with its default selections when installing and ended up with this:

Drive layout
/dev/sda1 -ntfs 128GB -boot
/dev/sda2 -extended 170GB -lba
 /dev/sda5 -ntfs 167.59GB
 /dev/sda6 -ext3 2.33GB
 /dev/sda7 -linux-swap 172MB

I'd like make the system dual bootable without having to reinstall windows (real pain since I would have to go through an obstructionist IT dept). I know I can make windows bootable with a rescue disk and fixmbr but is there something I can do to make it dual bootable using the ubuntu livecd?

Alternately, what should I have done at the partition stage of ubuntu installation to avoid this?


I would keep Windows' mbr in the mbr and try a partition layout like this:

Drive layout
  /dev/sda1 -ntfs 128GB -boot
  /dev/sda2 -ext3 3GB
  /dev/sda3 -extended 167GB -lba
      /dev/sda5 -ntfs 166.8GB
      /dev/sda6 -linux-swap .2GB

and when installing, install Grub on /dev/sda2.

Boot into windows and use Diskpart to set /dev/sda2 as active.


Using something like Partition Magic will allow you to move the other partitions down the 100MB or so that you'll need for your boot partition. 128GB is right around the threshold for "too far", and even if you manage to get grub to boot with the partition down there, there's no guarantee that it will continue to be able to do so if updated.

As always, backups are recommended before doing this.

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