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Superspeed500

macrumors regular
Original poster
Jul 25, 2013
198
45
I have an MacBook Pro 15 from mid 2010. My hard drive is on 320 gb. I have a Mac partition at 129,87 gb and a Bootcamp partition at 189,6 gb. both partions mount in Mac Os X. However the Windows partition won't boot. It shows an hard drive fault. I have managed to boot it into a black screen with supergrub 2.

The output of the fdisk "/dev/disk0" command returns the following output:
Code:
Disk: /dev/disk0	geometry: 38913/255/63 [625142448 sectors]
Signature: 0xAA55
         Starting       Ending
 #: id  cyl  hd sec -  cyl  hd sec [     start -       size]
------------------------------------------------------------------------
 1: EE 1023 254  63 - 1023 254  63 [         1 -     409639] <Unknown ID>
 2: AF 1023 254  63 - 1023 254  63 [    409640 -  253644760] HFS+        
*3: 07 1023 254  63 - 1023 254  63 [ 254316544 -  370821120] HPFS/QNX/AUX
 4: 00    0   0   0 -    0   0   0 [         0 -          0] unused

I have also installed GPT fdisk, wich gives the following output from the MBR partition table:
Code:
Disk size is 625142448 sectors (298.1 GiB)
MBR disk identifier: 0x00000000
MBR partitions:

Number  Boot  Start Sector   End Sector   Status      Code
   1                     1       409639   primary     0xEE
   2                409640    254054399   primary     0xAF
   3      *      254316544    625137663   primary     0x07

Please note that this table have the wrong disk size and partition size! Output from GPT partition table:
Code:
Disk /dev/disk0: 625142448 sectors, 298.1 GiB
Logical sector size: 512 bytes
Disk identifier (GUID): 52ADD3E2-B036-7640-9327-74D35743F5FB
Partition table holds up to 128 entries
First usable sector is 34, last usable sector is 625142414
Partitions will be aligned on 8-sector boundaries
Total free space is 266901 sectors (130.3 MiB)

Number  Start (sector)    End (sector)  Size       Code  Name
   1              40          409639   200.0 MiB   EF00  
   2          409640       254054399   120.9 GiB   AF00  
   3       254316544       625137663   176.8 GiB   0700

So it seems for me that the GPT and MBR is in sync, but they are both wrong. However Mac Os X boots perfectly with the correct drive values :eek:

What is wrong with the GPT/MBR and how do I fix it?

Status of GPT and MBR:
Code:
GPT fdisk (gdisk) version 0.8.7

Type device filename, or press <Enter> to exit: /dev/disk0
Warning: Devices opened with shared lock will not have their
partition table automatically reloaded!
Partition table scan:
  MBR: hybrid
  BSD: not present
  APM: not present
  GPT: present

Found valid GPT with hybrid MBR; using GPT.

It seems like my boot sector of my hard drive is corrupt. I have backup of my important windows files and I have full backup of Mac Os X Lion with Time Machine. I might be able to run winclone from a boot cd and clone the windows disk and then reformat the drive and clone back Windows and Mac Os X.

Thanks for all help :)

Edit:
I will now try to do the following steps to fix my partition tables:
1. Backup Windows and Mac (Clonezilla/Time machine)
2. Delete all partitions on drive.
3. Create Mac partition and recover Mac Os X.
4.Use bootcamp assistent to recreate Windows partition.
5. Use clonezilla to put Windows back.

This should recreate all partition tables while keeping all partitions in their current state.

I decided to put Windows on another computer, so I do not need any more help with this right now.
 
Last edited:
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