troubleshooting Question

BootCamp Partition - Lost Windows Partition MBR

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etronics6Flag for United States of America asked on
Mac OS XWindows 10Apple Hardware
3 Comments2 Solutions485 ViewsLast Modified:
I have been using BootCamp on my mac for years, with no issues.  About 6mo ago, I noticed I needed more space on my Windows Side, so I resized my partitions... everything seemed to go fine... I am running windows 10 on the Windows side & El Capitan on the Mac Side...

I really do not use the Mac side barely at all, but I want to be able to have both, the best of both worlds...

So basically I went to go onto my Mac side yesterday & rebooted into the Mac side, no problems!  Did what I needed to on that side & then went to Restart in Windows Partition & there is NO windows Partition anymore in the Startup Disk ... It just has the Mac OS X ... I am guessing I never saw any issue before this because I never went to the mac side...

I really don't want to have to do a FRESH install of both again... if I can help it...

IS THERE ANY SOLUTION  or an EASY FIX ( I know I am reaching... hoping & praying ) to get the MBR back in some way?  that is what it looks like as I was searching around...

I tried to do what this article said, but nothing changed...

When I restart & hold down the OPTION key, 3 choices come up, Mac OS X / Recovery / Windows, when I choose Windows it says, MISSING OPERATING SYSTEM...

I want to be able to at least get the data off the drive & really don't want to pull my iMac apart to get to the hard drive & then if the data is even there??

Will the data be there??  in Disk Utility I can see there 500gb of Untitled, but I know that was my Windows Partition, before I ever tried to resize... the resized partition should be 750gb I think...

Anyway, I hope someone can help...

This something else I ran, hopefully it will be helpful to someone that can read it & know what it is saying...

From Terminal:
Last login: Sat Aug  6 18:20:15 on console
Etronics6-iMac:~ etronics6$ sudo gpt -r -vv show disk0
gpt show: disk0: mediasize=1000204886016; sectorsize=512; blocks=1953525168
gpt show: disk0: Suspicious MBR at sector 0
gpt show: disk0: Pri GPT at sector 1
gpt show: disk0: Sec GPT at sector 1953525167
       start        size  index  contents
           0           1         MBR
           1           1         Pri GPT header
           2          32         Pri GPT table
          34           6        
          40      409600      1  GPT part - C12A7328-F81F-11D2-BA4B-00A0C93EC93B
      409640   591229312      2  GPT part - 48465300-0000-11AA-AA11-00306543ECAC
   591638952     1269536      3  GPT part - 426F6F74-0000-11AA-AA11-00306543ECAC
   592908488   384055096        
   976963584   976560128      4  GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7
  1953523712        1423        
  1953525135          32         Sec GPT table
  1953525167           1         Sec GPT header
Etronics6-iMac:~ etronics6$ sudo fdisk /dev/disk0
Disk: /dev/disk0      geometry: 121601/255/63 [1953525168 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 -  591229312] HFS+        
 3: AB 1023 254  63 - 1023 254  63 [ 591638952 -    1269536] Darwin Boot
*4: 07 1023 254  63 - 1023 254  63 [ 976963584 -  976560128] HPFS/QNX/AUX
Etronics6-iMac:~ etronics6$ diskutil list
/dev/disk0 (internal, physical):
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *1.0 TB     disk0
   1:                        EFI EFI                     209.7 MB   disk0s1
   2:                  Apple_HFS Macintosh HD            302.7 GB   disk0s2
   3:                 Apple_Boot Recovery HD             650.0 MB   disk0s3
   4:       Microsoft Basic Data                         500.0 GB   disk0s4
Etronics6-iMac:~ etronics6$

One other thing i did today was upgrade to El Capitan, thinking that would help matters... the disk utility looks different now, BEFORE El Capitan I could see the Disk0s4, now I get a graphic like this one I have embedded ... I can see the Windows partition, but now it doesn't have the Disk0s4 anymore on the left... now it is ALL TOGETHER...

 Disk Utility Partitions
I hope someone can help... thank u in advance for any assistance you can offer to get me to a solution!!
David Anders

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