Grub2 Not Booting into Windows 7 After Fedora 17 Install

I have a number of dual boot machines working fine with earlier versions of Fedora.  After a Fedora 17 install I get, along with at locale file error message flashing up

error: invalid signature
Press any key to continue

And Windows won’t boot.  Following the example in the posting I made the change of adding

set root=(hd0,msdos1)

and everything works just as it should. 

More Fedora 16 Grub2 Tips and Tricks

I resolved the core.img is unusually large problem by expanding the boot partition.

I was reinstalling a server yesterday and I found that Fedora 16 Anaconda will put a 1MB partition first in order to boot, before adding the 500MB (current standard) partition for /boot.


On the first machine, one of the tasks I completed in order to assist in troubleshooting was to create a USB key with Grub2 on it to boot the machine into Fedora.  That left me with Windows dual booting just fine and allowed me breathing space to troubleshoot and use gparted to solve my problem.

Put these Grub2 Linux bash commands into Diigo today so you have them when you need them.  A reminder that GNU GRUB is a work in progress and the information in this website is incomplete and may be wrong and/or out of date. Please consult the official GNU GRUB 1.98-r2692 manual as well.  Still I did use the commands for Grub on a USB and they worked after I translated configuration file locations from grub to grub2.

Fedora 16 Grub2 Fail with “core.img is unusually large”

I was upgrading to Fedora 16 on my Dell Dimension E520, originally loaded with XP, and all manners of problems occurred with Grub2.  The machine is set to dual boot Linux and Windows XP and has worked fine in this capacity while testing and using a number of Linux distributions including Fedora 14 and Fedora 15.

After upgrading, it began by requiring that grub2-install needed to be run everytime I rebooted.  By the time I really had a chance to look at it, updates rendered it foobar.

The error contained  your core.img is unusually large, it won’t fit in the embedding area and is readily found here.

The Dell has a RAID controller and although the disk is not using it, Bugzilla #737508 applies.  Essentially Grub2’s core image exceeds the 32KiB partition that was originally created.  Maddening as it is trivialized in the bug report as unlikely to happen, although if you haven’t repartitioned the entire disk to get a more popular 1MiB BIOS boot partition, it will happen.  The fix is straightforward, reduce the size of the following partition without sliding it forward, GParted on SystemRescueCD worked fine,  and a larger BIOS boot partition will be allowed.  Grub2 installs with no issues

NOTE: if you delete the next partition, and Windows follows it, you will not be able to boot Windows, nor load the Recovery CD, the boot.ini references a partition table that no longer matches and Windows drops the blue screen of death from a CD boot.  The confusing %windows%/system32.hal.dll errors is provided off a hard disk boot.  Simply add back a small EXT2 partition (assuming what you found was the small VFAT partition DELL installs with the machine) which has a smaller allowed size and everything will run just great.

Changing Boot Sequence in Grub2

I just loaded Fedora 16.  I have this odd Dell Inspiron with a WinTV Express Card, the only card ever built for this slot.  To simplify my life I run Windows 7 for TV and Linux for everything else.

Where was I?  How to alter the boot sequence in grub2

# cat /boot/grub2/grub.cfg |grep Windows


# menuentry “Windows 7 (loader) (on /dev/sda3)” …

Set this menuentry as default

# grub2-set-default “Windows 7 (loader) (on /dev/sda3)”

You can see the default entry with

# grub2-editenv list

And this worked.

I have since found that I should have generated an updated grub.cfg

# grub2-mkconfig -o /boot/grub2/grub.cfg