Grub2 - unable to boot Windows 7

[satellite360]

Hi all

Just installed Windows 7 and Ubuntu 9.10 on 2 separate HDDs. Windows 7 boots fine when I detach the Ubuntu HDD but fails to boot from grub2.

Updating grub2 gives the following error:

$ sudo update-grub2
Generating grub.cfg ...
Found linux image: /boot/vmlinuz-2.6.31-14-generic
Found initrd image: /boot/initrd.img-2.6.31-14-generic
Found memtest86+ image: /boot/memtest86+.bin
Found Windows 7 (loader) on /dev/sdb1
grub-probe: error: Cannot find a GRUB drive for /dev/sdb1. Check your device.map.

done

The device map shows only this:

$ cat /boot/grub/device.map
(hd0) /dev/sda

fdisk output:

$ sudo fdisk -l /dev/sda

Disk /dev/sda: 320.1 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x9b36db89

Device Boot Start End Blocks Id System
/dev/sda1 * 1 2562 20579233+ 83 Linux
/dev/sda2 38787 38913 1020127+ 82 Linux swap / Solaris
/dev/sda3 2563 38786 290969280 83 Linux

Partition table entries are not in disk order


$ sudo fdisk -l /dev/sdb

Disk /dev/sdb: 320.1 GB, 320072933376 bytes
255 heads, 63 sectors/track, 38913 cylinders
Units = cylinders of 16065 * 512 = 8225280 bytes
Disk identifier: 0x2f2d153b

Device Boot Start End Blocks Id System
/dev/sdb1 * 1 13 102400 7 HPFS/NTFS
Partition 1 does not end on cylinder boundary.
/dev/sdb2 13 10396 83398656 7 HPFS/NTFS
/dev/sdb3 10396 38914 229067776 7 HPFS/NTFS

Any idea what I need to do to get grub2 to boot Windows 7 (/dev/sdb2)?

[satellite360]

I solved this by adding the following to /etc/grub.d/40_custom

menuentry "Windows 7 (on /dev/sdb1)" {
insmod ntfs
set root=(hd1,1)
chainloader +1
}
No idea why the os-prober is not adding the correct details but until grub2 is fixed this workaround will do.

[yaiyuy8W]

Thank you!

This fixed my infinite Windows 7 and Vista boot loop!

[crowdofone]

This looks very similar to the solution i hit on where it would boot if i placed an extra entry in /etc/grub.d/40_custom that was a copy of the Windows 7 entry from grub.cfg with the highlighted red text removed.



menuentry "Windows 7 (loader) (on /dev/sda1)" {
insmod ntfs
set root='(hd0,1)'
search --no-floppy --fs-uuid --set 2cb8b1f1b8b1b9a2
chainloader +1
}


In my case i think the search parameter has to be included but the following --no-floppy & --fs-uuid were optional.

I also needed to run update-grub after to rebuild grub.cfg

.

[garvinrick4]

I solved this by adding the following to /etc/grub.d/40_custom

menuentry "Windows 7 (on /dev/sdb1)" {
insmod ntfs
set root=(hd1,1)
chainloader +1
}No idea why the os-prober is not adding the correct details but until grub2 is fixed this workaround will do.
I do not believe grub2 is broken as long as you put grub into sda or sdb. It is a little trickier if you add Windows second. If you copy grub from a viable / and into sda or sdb wherever it is needed with a live CD it works like a charm. You have Windows first install it gets overwritten by grub when Linux installed 2nd never notice and works without touching it. Linux internal, Windows USB and wanting grub2 to work out of box without installing it is pretty tough on grub2. Glad you got her fixed up. Have a nice day.

[en666]

None of above solutions worked for me. With these solutions Windows7 boots once, then i have to redo update-grub to make the menuentry work again.
I registered an account here only for comunicate you that I found a definitive solution. I use ubuntu 10.04 but I think that it's ok for all distros.

http://erickoo.wordpress.com/2009/06/14/how-to-add-vista-partition-to-grub-2-ubuntu-9-10-karmic-koala/

10.04 :guitar:s!