Uninstall GRUB boot loader!


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Is there a way to uninstall the GRUB boot loader either through a live Linux CD or some diagnostic boot CD?

Currently I've used my Toshiba restore disk to reformat my system--removing partitions containing Linux--but unfortunately it didn't do anything to the MBR, so now I have a system that will never load any OS and goes into an endless cycle of reboots whenever I hit the power button.

Any help will be greatly appreciated. Thanks in advance

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You need to overwrite the boot sector of your partition, and the only way to do that is to use the Recovery Console and run fixboot (not fixmbr). You could also install Windows again, which would recreate the boot sector, but then you'd have an extra Windows installation...

Either way, you'll need a Windows CD, so go find one, even if it's a friend's (Y)

I've always just had to use FIXMBR and had it work every time. However, I'm not sure what you can do if you don't have the CD.

There might be the possibility that you can use a win98 boot disk and do the fixboot command. that might work... not sure...

  Fit4130Rider said:
There might be the possibility that you can use a win98 boot disk and do the fixboot command. that might work... not sure...

No, that won't work. Windows 98 boot disks don't contain ANY NT files, and as such are practically useless on NT/2000/XP machines because they run DOS. The Recovery Console is technically NT, AFAIK.

  John said:

No, that won't work. Windows 98 boot disks don't contain ANY NT files, and as such are practically useless on NT/2000/XP machines because they run DOS. The Recovery Console is technically NT, AFAIK.

I do have a very old Windows NT CD. Maybe that'll work?

Or, alternatively, should I just reinstall a version of linux to get a bootloader and then uninstall the boot loader from within linux? I'd get a "Missing operating system" message the next time I boot, but I've gotten that before and the recovery disk was somehow able to correct that problem.

Again, any help would be greatly appreciated.

You have access to the i386 folder anywhere on your hard disk or a restore cd? from windows start > run > (path to i386 folder)\winnt32.exe /cmdcons will install the recovery console which can be accessed when you next boot. Then remove the grub loader as described above

  Jason He said:

what about just installing Linux and removing the MBR completely from that os? would that work?

I doubt it because you'll be left without a mbr rather than it returning to the original windows one. I think you'll have an easier time finding a copy of windows xp home (i presume)

  the_upsetter said:
I doubt it because you'll be left without a mbr rather than it returning to the original windows one. I think you'll have an easier time finding a copy of windows xp home (i presume)

I am pretty sure that it has to be XP Pro, as XP Home does not include the Recovery Console, so you cannot do the fixmbr thing.

I had a similar problem last night when trying a dual boot with Ubuntu and XP Pro. To fix it, I used a Mandrake install CD to get into the partitioner, blitzed all the linux partitions, setup a temp Linux partition, put Mandrake on (with LILO overwriting GRUB at the mbr) and then used the rescue mode of Mandrake to restore the XP bootloader.

That got me into Windows and then I removed the Linux partition using Partition Magic. Now back to XP Pro (single boot) and no problems whatsoever.

  the_upsetter said:

I doubt it because you'll be left without a mbr rather than it returning to the original windows one. I think you'll have an easier time finding a copy of windows xp home (i presume)

Yes, I would be left without an MBR, but the recovery disk appears to be able to repair it.

You could get a GRUB boot disk in order to get into windows. Then do the C:\ <path to i386> \winnt /cmdcons thing, I've done that and it works. When you reboot, it will need the GRUB boot disk again, and then it will give you the menu for XP or Recovery Console. Log in to the RC, and type fixmbr. Voila, done.

I'm pretty sure grub boot disks can boot to a hard drive, anyway.

And is anyone else wondering why this is in XP Client?

Also, sorry to say this mark, but XP Home does have the RC. I've used it.

There are also RC bootable disks, without the OS on it.

  the_upsetter said:

Does it not? Blimey that's a bit of a loss! Best of luck with the Linux route Jason

I suppose I could borrow a friend's XP Home or Pro CD, but i'd rather do it myself.

The problem was, when I used a SUSE Live CD to uninstall the boot loader, it didn't actually complete the operation. When the YAST2 module loaded to give me access to boot loader options, it said that there was a partitioning problem :rolleyes:

If anyone can boot a Linux LiveCD on a Windows box, they can use the dd command to copy out the MBR boot info (however many bytes that is, 446 or something), then you can use a Linux LiveCD to use the dd command to re-write it to your drive without needing to find any other utiltites.

EDIT: Yes, it is 446 bytes: http://www.diydatarecovery.nl/mbr.htm

The command dd if=/dev/hda of=/dev/hda1/mbr.bin bs=446 should work to read the MBR, and place it in a file called "mbr.bin" in the root directory of your first partition (assuming your LiveCD can write to it). You can pick a floppy or some other device, too.

You would have to get a copy of the MBR from another PC. You could do it yourself, if you have another PC.

Disclaimer: I have *NEVER* tried this personally, so cannot vouch that it will work.

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