HOWTO: Restore GRUB (if your MBR is messed up)

[frank cox]

Hi:

I have a Dell duo-core with 2 gb of ram and a 500 gb hd.
I was messing around with the partition copy in Puppy Linux and thought it would just create a file on a partition, instead it locked the partition.

My machine has [had?} XP on the first partition then Ubuntu on the other three . Ubuntu 9.04 still works but I cannot open XP. Is there any way to fix that?

[_mikec_]

i jus get bootmbr missing, press ctrl+alt+del to restart no matter how much i play with the boot order... so i can hardly get to the live installation part

Have you tried to fix the MBR using a windows installation cd ? with the fixmbr dos command ? this is only a guess since i never had this problem before and each time i had any problems with the MBR while running Windows XP i've boot the machine into dos and use the "fixmbr" command available.

[_mikec_]

Hi:

I have a Dell duo-core with 2 gb of ram and a 500 gb hd.
I was messing around with the partition copy in Puppy Linux and thought it would just create a file on a partition, instead it locked the partition.

My machine has [had?} XP on the first partition then Ubuntu on the other three . Ubuntu 9.04 still works but I cannot open XP. Is there any way to fix that?

maybe try Puppy Linux to unlock it ?, this has nothing to do with Ubuntu, your problem is with Puppy Linux and Windows.

[frank cox]

maybe try Puppy Linux to unlock it ?, this has nothing to do with Ubuntu, your problem is with Puppy Linux and Windows.

Well it does have something to do with Ubuntu, it is the grub that is corrupt and the grub is in Ubuntu.

[_mikec_]

please post /etc/grub/grub.cfg

[perspectoff]

avoid? hell, for a newbie prior to actually being booted into whatever distro, commandline is virtually impossible, it's plain wilderness stuff.

These are cut and paste instructions, mate. Perhaps you should join Hare Krishna. They'll take care of you if you've had too many drugs to cut and paste.

[margazhang]

This thread is too long and I cannot go through all posts. So I don't know if someone has already posted the fix.

Anyway, I changed hard drives a few times and that gave me this error:

error: biosdisk read error

Inserting a floppy disk into the floppy drive made this error gone upon reboot but I could not boot from the boot menu (if everything works fine this boot menu should not have shown up) as it mis-identifies drives.

The simplest fix is this...

I booted from the Ubuntu 9.10 live CD and then chose the last item on the list - "Rescue a broken system" to repair the GRUB. It just tried to "Reinstall GRUB boot loader" although it failed to reinstall.

Anyway, after this I could access the boot menu without the liveCD. I then picked to boot in rescue mode and then picked to update grub.

Then I have no problem booting normally! So 9.10 liveCD does repair GRUB when you encounter booting problems. That is great!

Ooops, I have problem rebooting again! Got to look for a fix

Hmmm... I download Super Grub Disk iso file, burn it on a CD and boot from this Super Grub CD. I tried a few things with it and then I can boot again in the rescue mode and fixed the problem. Now I am OK now - Thanks to Super Grub!

[Gaga0309]

Hi everyone, I think I'm having a similar problem. I need Help!! I had a triple boot (Vista/XP/Ubuntu) prior to 9.10 Update. Now my Vista desktop fails to load (solid blue screen) beyond password prompt since 9.10. My Ubuntu 9.10 & XP boots perfectly fine. XP is on secondary IDE HD. Vista & Ubuntu are on Primary 500GB SATA HD. Boot table appears to be normal. This setup was done by my brother who is now deployed overseas & I am a complete linux noob. Please help someone?? Anyone ???

[margazhang]

If XP is working fine, why still using Vista? Just boot into Ubuntu and grab all the data you need it - if you install Ubuntu properly, it should be able mount both your XP and Vista partition automatically. This means that you can access both your XP and Vista partition from Ubuntu.

I would not do triple boot again. In my case I run Windows XP inside Ubuntu via VirtualBox.

[Pelsia]

Shortly I'm going to need to reinstall my windows partition, currently its set to dual boot with XP and Ubuntu 9.04; everything is working fine actually. There's an application I need to install but some registry keys crucial to its functionality are missing. Restoring the registry from the cd will fix the problem, but pretty much break everything. And there way too many keys to add manually, would take longer than a fresh install takes.

So.....before I undertake this I'll see if the program works with wine; last time I checked someone managed to get it partially functional which could be enough, in which case I'll ditch XP all together (only reason for dual boot is cuz it's a laptop, otherwise would use removable drives). When I install XP or Vista I know its going to most likely nuke the mbr. If I leave the Ubuntu partition alone (not that I had any intentions of changing it) during the windows install process, will fixing the mbr as described on the first page be all I need to do? Or will I need to tarball Ubuntu up and then restore it later using a bootable disk?