Gentoo Forums
Gentoo Forums
Gentoo Forums
Quick Search: in
windows steals MBR every time it boots
View unanswered posts
View posts from last 24 hours

 
Reply to topic    Gentoo Forums Forum Index Installing Gentoo
View previous topic :: View next topic  
Author Message
braver
n00b
n00b


Joined: 29 Dec 2006
Posts: 28

PostPosted: Fri Jan 26, 2007 8:15 am    Post subject: windows steals MBR every time it boots Reply with quote

Every time I dual-boot into Windows XP, it steals MBR, so I had to install GRLDR -- Grub for Windows -- which sees my menu.lst. But I have to be alert and catch the boot process. How do I prevent Windows from grabbing MBR back?
Back to top
View user's profile Send private message
slycordinator
Advocate
Advocate


Joined: 31 Jan 2004
Posts: 3065
Location: Korea

PostPosted: Fri Jan 26, 2007 8:28 am    Post subject: Re: windows steals MBR every time it boots Reply with quote

braver wrote:
Every time I dual-boot into Windows XP, it steals MBR, so I had to install GRLDR -- Grub for Windows -- which sees my menu.lst. But I have to be alert and catch the boot process. How do I prevent Windows from grabbing MBR back?


As part of the installation of windows it writes a windows-compatible mbr, so unless you're gonna rewrite windows' installation program so that when you do a full reinstall that it doesn't clobber the mbr you're gonna have to do something like either reinstalling grub afterwards or using something like GRLDR.

Also, you don't have to be all that alert and catch the boot process. All you do instead is change the default thing that ntldr boots from to booting from GRLDR.
Back to top
View user's profile Send private message
braver
n00b
n00b


Joined: 29 Dec 2006
Posts: 28

PostPosted: Fri Jan 26, 2007 8:57 am    Post subject: Reply with quote

No -- it grabs MBR every time after I boot into windows. That is, instead of GRUB, I get Windows NTLDR. I managed to install GRLDR so I have it, and can indeed make it default. But I don't like Windows to overwrite GRUB every time I *boot* into windows (not install it)! Is it normal?
Back to top
View user's profile Send private message
slycordinator
Advocate
Advocate


Joined: 31 Jan 2004
Posts: 3065
Location: Korea

PostPosted: Fri Jan 26, 2007 9:31 am    Post subject: Reply with quote

I've never heard of this happening.

I'm betting there's something more happening. Perhaps you've got grub installed on a disk different than the one that is being booted from so that it's been installed to the mbr of the wrong disk?

Like it's possible that you told grub (when you were in the livecd) to install to (hd0) whereas when you actually boot from disk the real first disk isn't the one that grub was installing to.

I had that happen once.
Back to top
View user's profile Send private message
braver
n00b
n00b


Joined: 29 Dec 2006
Posts: 28

PostPosted: Fri Jan 26, 2007 8:33 pm    Post subject: Reply with quote

The setup is very simple -- I have a laptop, a tablet PC with only the internal drive, /dev/hda. Windows is in the first partition, then there's another partition, a bunch of Linuxen partitions... From any Linuxen I mount the same /boot, and grub is installed by

grub-install /dev/hda

-- after I do that, reboot shows GRUB, but if I ever boot into Windows, they steal the boot, and the next time it's NTLDR!
Back to top
View user's profile Send private message
Rukie
l33t
l33t


Joined: 26 Jan 2004
Posts: 692
Location: SE Wi, Home of cheese and cowtippers.......

PostPosted: Sat Jan 27, 2007 5:07 am    Post subject: Reply with quote

I had a similar problem with my computer.
Have you tried going into the grub command prompt
# grub

and then installing it manually into the mbr instead of the boot partiton?
(Or are you already doing that?)

root (hd0)
setup (hd0)

worked for me inside of the grub prompt, rather than using a boot partiton like (hd0,0)
_________________
Gentoomania! Support the Open Source!
http://www.rukie.ath.cx
Back to top
View user's profile Send private message
lagalopex
Guru
Guru


Joined: 16 Oct 2004
Posts: 562

PostPosted: Sat Jan 27, 2007 10:01 am    Post subject: Reply with quote

Whats in you grub.conf / menu.lst? What does "fdisk -l /dev/hda" tell you about the active/boot flag?
Are there any "systemtools" or "av-programs" running in windows? Was there any update of windows which could have caused this problem? Is it happening in the "safe-mode" of windows as well?
....
Back to top
View user's profile Send private message
kel_p
n00b
n00b


Joined: 05 Feb 2007
Posts: 31
Location: Amsterdam

PostPosted: Sun Feb 11, 2007 10:49 pm    Post subject: Reply with quote

slycordinator wrote:

I'm betting there's something more happening. Perhaps you've got grub installed on a disk different than the one that is being booted from so that it's been installed to the mbr of the wrong disk?


That's what I'm thinking also..

Also.. you can always bypass the windows bootmanager by making one entry default (normally there is just one), and disabling the counter.
Back to top
View user's profile Send private message
quad
n00b
n00b


Joined: 23 Jan 2007
Posts: 19

PostPosted: Mon Feb 12, 2007 10:03 pm    Post subject: Reply with quote

lagalopex wrote:
Are there any "systemtools" or "av-programs" running in windows? Was there any update of windows which could have caused this problem? Is it happening in the "safe-mode" of windows as well?
....


I tend to think that lagalopex is at least partially right, if not fully. Windows itself or antivirus programs may very well check the MBR for any modification from the normal Windows loader. Any inconsistency would be thought of a virus trying to hide itself in the MBR and it would get overwritten any time Windows boots. May as well be one of those vendor-supplied programs doing pretty much the same check to ensure that Windows is still bootable on the notebook. I'd say follow this path and see what you can find.
Back to top
View user's profile Send private message
madisonicus
Veteran
Veteran


Joined: 20 Sep 2006
Posts: 1130

PostPosted: Mon Feb 12, 2007 10:10 pm    Post subject: Reply with quote

I'd like to see your grub.conf if you're still having this problem. I may be behind the times, but I just discovered grub-set-default, and it's magical ability to change the default boot behavior. I have to wonder if this might be part of what's going on.
_________________
Please add [SOLVED] to your message title if you feel that your question has been answered.
------
Intel Q9300 Core2 Quad * Gigabyte GA-EP35C-DS3R
Samsung x360
AMD64 x2 4200+ * TF7050-M2 * HTPC
ZOTAC ION A-U Mini-ITX * HTPC
Back to top
View user's profile Send private message
Display posts from previous:   
Reply to topic    Gentoo Forums Forum Index Installing Gentoo All times are GMT
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum