Dual boot problem - Vista disappeared from Grub menu

[Colin Law]

On 21 September 2010 20:42, Goh Lip <g.lip at gmx.com> wrote:
> On Wednesday 22,September,2010 12:43 AM, Colin Law wrote:
>>> Colin, try the following
>>> >  sudo grub-mkdevicemap
>>> >  sudo update-grub
>> Thanks for the help.
>> OK, did that, no change.
>>
>>> >
>>> >  You should check if you can boot up windows if you do the following at
>>> >  the grub prompt (press 'c' at grub menu)
>>> >  set root=(hd0,x)
>>> >  chainloader +1
>>> >  boot
>>> >
>>> >  where (hd0,x) is /dev/sdax of the windows partition, (usually x=1)
>> This boots into Vista ok.  So that means that Vista is ok, but for
>> some reason grub does not see it.
>> I see from the grub docs that I can manually include the relevant boot
>> option, but it would be better if I could persuade grub to work it out
>> for itself.   Any ideas where to go next?
>
> Colin, boot into ubuntu  and
> sudo grub-install /dev/sda

It said it installed successfully and I did sudo update-grub after,
but it is still not finding Vista.  Perhaps I have found a bug.  I
think I will go down the manual route using /etc/grub.d/40_custom as
described in https://help.ubuntu.com/community/Grub2

Thanks for the help anyway.

Colin