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I was trying to create an extra partition to get a file from the Windows side of my Macbook Air to the Mac side, and I accidentally made the disk dynamic without realizing it. I am now unable to boot to the Mac side (holding Alt to go into the system manager at startup doesn't even list the Mac partition), and the Windows side blue screens during boot (goes so quickly that it doesn't even get to the error code before restarting).

What can I do to fix the issue? I don't know how to make a bootable flash drive that a Mac will recognize, and Disk Utility (via Internet Recovery) couldn't do anything.

(cross-posted from apple.stackexchange)

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FYI: I don't believe what comes up when you hit alt/opt at boot is called the "System Manager"; you may be confusing it with the System Management Controller. – kalaracey Mar 6 '13 at 1:07
(1) This link may be of use to you. (2) Also, please add to your question what info exactly Disk Utility gave you (was the OS X partition still there, was it greyed out, what did you do, what messages did it give you, what it said your partition layout was). (3) Also, I guess your Recovery Partition is still there, that's a start. (4) Could you please give a little list of what your partition layout was? – kalaracey Mar 6 '13 at 1:12
(5) Did you perhaps convert your entire hard drive into a Dynamic Disk? (6) These links may be of use to you: 1 2 (7) If you are unable to recover your system, if you have another Mac, you may be able to setup your broken Mac into Target mode, so that you can get any valuable data off of it before reformatting. – kalaracey Mar 6 '13 at 1:19

I managed to solve my problem.

  • Burned a Fedora live CD and booted my desktop to that live CD.
  • Used livecd-iso-to-disk to create a live USB, as the Macbook Air doesn't have a disc drive (had to su -c 'yum install livecd-tools' first, then used the command su -c "--format --reset-mbr --efi /run/initramfs/livedev /dev/sdb")
  • Opened the boot menu by holding alt/option as the computer booted, then selected the EFI Boot option, which booted from the flash drive
  • Once in the Fedora, I downloaded TestDisk and ran it according to these instructions (important to note, however, that I had to select EFI GPT as the partition table type, not the Intel that was detected by TestDisk). It immediately picked up all of the partitions, then I hit enter, then hit write. After rebooting, everything was back to normal, and, as an added bonus, my extra partition functions as intended.
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I did something similar to the original poster, except I used GParted's liveCD as a live USB (it contains TestDisk).

It was really important to pick EFI GPT for the partition table type. Not Mac, not Intel, but EFI GPT. Anything else doesn't find your partitions and searching for them takes a LONG time.

Additionally, once I found my partitions almost instantly after picking EFI GPT, I had a whole bunch of phantom partitions that it was clear I didn't want; their sectors started and ended in the middle of other partitions, they were the wrong size, and TestDisk labeled them with sad red lettering. Partitions with the right size, location, and the same name were still there, in happy green lettering. I tried to add one of the weird ones to the write list and TestDisk wasn't happy, so I left them out. That wasn't extensively covered in the Test Disk documentation, so I wanted to mention it. This proved to be the correct choice for anyone freaking out about not writing a partition to the partition table.

Everything worked fine, and like the original poster, my swap partition works as intended. As a bonus, the friend whose Mac I almost killed is still my friend. I probably should have guessed that trying to resize my windows partition from inside windows and thus making a dynamic disk was a BAD IDEA and should have used GParted in the first place, but this worked out in the end.

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