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Gparted fuxored my ability to boot Windows!


erbic
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I decided I wanted a smaller Windows partition and larger Mac partition, but I didn't really feel like wiping my Boot Camp install to do so.

 

I've used Gparted LiveCD in the past on several PCs, with no issues. According to the site, it works with most/all x86 hardware. Seeing this, I downloaded the latest build in order to resize my NTFS partition and extend my HFS+ partition. Gparted is supposed to be able to do this.

 

It was able to see all the partitions on my HDD, so I told it to shrink my NTFS partition from 40 gigs to 30. In doing so, that 128MB of space Boot Camp leaves between the partitions would become about ten gigs of space. Everything seemed to go fine.

 

Before trying to extend my HFS+ partition, I decided to boot Windows/Mac up to make sure nothing got fuxored. Lo and behold, my Windows partition doesn't show up when holding option on boot.

 

The data is still there, as I can see it in Mac OS and mount it read/write with MacFUSE. Just can't boot Windows for reasons unknown. And Gparted wouldn't let me extend the HFS+ partition to fill the free space, and gave me errors when I tried to put the NTFS partition back to its original size.

 

It's all a moot point now, as I used Boot Camp to delete the partition(thank god it worked still) and started over. But why would this have happened? I didn't think EFI would have a problem being able to see a second partition after a large amount of unallocated space, but it can't see it..

Edited by ErBiC
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EFI isnt the problem here, but rather GPT. GPT (GUID Partitioning Table) is a replacement for the aging MBR (Master Boot Record) system used on x86 PCs. It writes valid MBR information to where MBR-based OSes or programs expect to find it, for legacy compatability purposes. However, a side-effect of this is that disk utility programs like gparted think they can modify the MBR information, whereas in fact it is overwritten by GPT.

 

Sounds like gparted tried to {censored} with the MBR info on the disk, which confused GPT, leading to a non-bootable windows volume. Sounds like you recovered ok, but this is a good lesson for others: only use utilities which are GPT aware to prick with your (real) intel mac's disk.

 

(NB: GParted is 'safe' (relatively speaking) to use on a hackintosh system, as they all use MBR).

(NB2: Unless you have multiple hard disks in use on your hackintosh, in which case you might be using GPT on any non-boot volumes. Use Disk Utility to check. For example I have a 100Gb boot disk using MBR, and a RAID-1 mirror using two disks which use GPT.)

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Is there any open-source/GNU (read:free) partitioning software that IS GPT aware? Backing up and restoring images takes several hours (and is really :censored2: annoying), and I have next to no money of my own at the moment for a utility like iPartition.

Edited by ErBiC
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  • 2 years later...
Is there any open-source/GNU (read:free) partitioning software that IS GPT aware? Backing up and restoring images takes several hours (and is really :thumbsup_anim: annoying), and I have next to no money of my own at the moment for a utility like iPartition.

 

You could try gdisk. I'm not sure about what features it has, but I used it to print out MBR and GPT info about my disks.

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  • 4 months later...

Hey guys... Looks like I have found a solution to this precise problem.

 

Firstly, here's a description of the problem i personally had. I installed bootcamp and win7 with 50 gigs. I later decided I needed more space. I shrunk my HFS+ partition using disk utility in mac osx, then I used gparted live cd to resize my win7 partition.

 

Once I had done that I realized the err of my ways, and tried to use the win7 install disk to rescue the installation. No dice. I then stumbled upon the real solution:

1. Install reFIT

2. reboot

3. run the partition tool from the main menu (say yes to whatever it asks)

4. reboot

5. run it again (partition tool, say yes again)

6. insert your win7 install disk, and boot it.

7. run a repair.

8. reboot, and you're welcome :-)

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  • 4 months later...

I realize this thread is pretty old, but I thought I'd share some of my experience for anyone who stumbles on to this problem/thread.

 

 

Gparted *is* gpt aware (at least now in 2010 it is). The problem is that its behavior conforms to the spec—it makes a "protective" mbr table with one partition the size of the disk so that non-gpt aware software doesn't think it's unformatted. Unfortunately, Apple's bootcamp instead uses a non-standard hybrid MBR/GPT scheme so that the Window's side is booted with an emulated bios from the MBR. Thus, to restore the ability to boot into windows after using a program like gparted to edit the gpt, one must correct the mbr to reflect the proper partition divisions (though, you only really need to put the windows partition in there (on second thought, the read only hfs drivers probably need the mac partitions in the mbr to work)). This can be accompished manually with osx's fdisk or slightly more automated with gdisk / 'gpt fdisk'. The gdisk hybrid feature does not work quite the same way that OS X's hybridization does, but it works and restores the ability to boot into windows.

 

Also to note, if you use VMware to virtualize your bootcamp partition as well, you will need to update it's "MBR" for the virtual disk it creates to boot off of. The easy way to do that is to delete and recreate the vm from the newly sized partition but you can also do it manually by fdisking one of the virtual disk file.

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  • 1 year later...

Hey guys... Looks like I have found a solution to this precise problem.

 

Firstly, here's a description of the problem i personally had. I installed bootcamp and win7 with 50 gigs. I later decided I needed more space. I shrunk my HFS+ partition using disk utility in mac osx, then I used gparted live cd to resize my win7 partition.

 

Once I had done that I realized the err of my ways, and tried to use the win7 install disk to rescue the installation. No dice. I then stumbled upon the real solution:

1. Install reFIT

2. reboot

3. run the partition tool from the main menu (say yes to whatever it asks)

4. reboot

5. run it again (partition tool, say yes again)

6. insert your win7 install disk, and boot it.

7. run a repair.

8. reboot, and you're welcome :-)

-

This information absolutely saved me! I used Gparted to increase the size of my Bootcamp (Windows 732bit SP1) partition on a Macbook Air 2011 running Lion. Atfer resizing it, I couldn't boot into windows, and EVERY type of recovery disk I tried simply didn't work. I read at least 10 articles online all of which said "pop in the recovery disk, repair, and it will work!"

 

Unfortunately, the error I was getting was: "This version of System Recovery options is not compatible with the version of Windows you are trying to repair"

 

No matter what, I kept getting that error. Even worse, I downloaded Recovery Disks, OEM WIN7 ISOs for 32 & 64 bit...burned each one to USB 1 by 1 (have to use USB, cd-rom didn't work for some reason with Lion and Macbook Air) and still nothing worked.

 

The error I was getting when I tried to boot up Windows was:

No bootable device -- insert book disk and press any key

 

Finally I stumbled upon this article, but only AFTER my friend (who knows Mac OS much better than I) tipped me off that Lion was detecting the partition as GPT not MBR.

 

So... if you try to resize your windows 7 partition on your macbook air SSD and run into the same nightmare I did ...try this:

 

Download ReFit on your mac

Install in

Reboot and a ReFIT menu should pop up before you enter the Max OS

Select the "partition tool" or something like that....

It should detect that your Bootcamp partition is incorrectly marked as GPT, it will ask you to confirm changing this to MBR, press y

Reboot again

ReFit again

Run the tool again

Reboot again, but this time have your windows recovery disc and/or installation disk inserted already

Click "Repair the install"

It will immediately rpair the problem... and now you can boot into Windows.

 

Whew.

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