Ruled out ntfs corruption with CHKDSK. Then I installed 10.04.2 wubi and it boots fine on /dev/sda3. So there appears to be something about the Natty where /host is not the main Windows partition.
PS before I removed the Natty install, I ran updates and it stopped booting again - dropping at the grub prompt.
This is the section of grub.cfg that differs from a lucid 10.04.2 grub:
function load_video {
true
}
insmod part_msdos
insmod ntfs
set root='(/dev/sda,msdos3)'
search --no-floppy --fs-uuid --set=root 8654915254914639
loopback loop0 /ubuntu/disks/root.disk
set root=(loop0)
if loadfont /usr/share/grub/unicode.pf2 ; then
set gfxmode=auto
load_video
insmod gfxterm
fi
terminal_output gfxterm
Ruled out ntfs corruption with CHKDSK. Then I installed 10.04.2 wubi and it boots fine on /dev/sda3. So there appears to be something about the Natty where /host is not the main Windows partition.
PS before I removed the Natty install, I ran updates and it stopped booting again - dropping at the grub prompt.
This is the section of grub.cfg that differs from a lucid 10.04.2 grub:
function load_video {
true
}
insmod part_msdos /dev/sda, msdos3) ' disks/root. disk grub/unicode. pf2 ; then
insmod ntfs
set root='(
search --no-floppy --fs-uuid --set=root 8654915254914639
loopback loop0 /ubuntu/
set root=(loop0)
if loadfont /usr/share/
set gfxmode=auto
load_video
insmod gfxterm
fi
terminal_output gfxterm