Mac is unable to boot due to wrong partition format

[Blackhawk]

Hello,
I have an iMac (21.5-inch, late 2013, running OS X 10.10.4) with Windows 7 as dual boot installed.
I created a new partition on Windows and everything worked fine, but as soon as I rebooted my Mac it was unable to boot OS X or Windows.
I started the Mac in recovery mode to check what's wrong and the disk utility showed that all partitions are in a format called "Windows_ldm" and I couldn't do anything else because the partitions were grey and I couldn't select or repair them.
Then I booted from a Linux stick to check whether my data still exist and yes they do, I can access all files on the boot camp partition but not on the OS X partition because I encrypted it some time ago. Furthermore the Linux terminal recognizes the partitions with a type called "SFS" (not windows_ldm).

My question now is, is there any way to convert those windows_ldm/SFS partitions back to the normal OS X format without losing any data or at least access the encrypted OS X partition's files to save them.

I'd appreciate any help, thank you.

 

[Cory Cooper]

Hello and welcome.

-How did you create the hard drive partitions?
-Are you using Boot Camp?

C

 

[Blackhawk]

Hello and welcome.

-How did you create the hard drive partitions?
-Are you using Boot Camp?

C

The first partition is the normal OS X partition, the second one was created with boot camp or using OS X disk utility and the third one which probably caused the problem was created using Windows' built-in disk manager.

Yes I'm using boot camp.

 

[Cory Cooper]

I believe the issue was caused by using the Windows built-in disk manager to create the third partition.

I will have to do a little more research, but my initial thought is that you will have to do a complete erase and install of the entire hard drive to correct things. But, don't do anything yet, until we dig a little deeper.

Do you have a Time Machine or other backup of your data?

C

 

[Blackhawk]

Unfortunately, I have no backup which is the problem, because with backup I could easily reinstall OS X. I could save the data on the Windows partition using a Linux stick but as I already said I can't do the same for the OS X partition because it's encrypted.
Thanks for your help.

 

[Cory Cooper]

-So, you can't see your files in OS X because it is encrypted?
-Was FileVault enabled in Mac OS X?

C

 

[Blackhawk]

Yes I can't see my files because the OS X partition is encrypted and yes, I encrypted it using FileVault so it was enabled.
I admit, enabling FileVault wasn't a good idea.

 

[Cory Cooper]

Yeah, FileVault is pretty much never a good idea. I wish Apple would either fix it or remove it.

This is definitely a tough situation. I don't want to suggest anything further, as I haven't run across all of these things simultaneously before. I don't want you to lose your data in the OS X partition, but I can't logically see any way around it.

I don't think an Apple Store Genius Bar could help out either, as this is outside their normal range of support/experience. We really need a nerd of a higher level here.

Let me think on it some more...

C

 

[Blackhawk]

Today I've been in an Apple Premium Reseller store their repair service wanted 114€ just for trying to restore the data and I don't think it's worth to pay that much for some hope. Well looks like I'll have to delete my stuff, luckily the only important thing I don't want to lose on my OS X partition is my nearly finished app. Time to recode it
Also I bought a 2TB HDD to prevent this in future.

 

[Blackhawk]

For others with a similar problem, it's possible to get the Windows partition working with a tool called Testdisk, it can be used with a Linux USB stick. With this tool, you are able to change the partition type from windows_ldm to FAT32 without losing any data.

And thanks a lot Cory Cooper for trying to help me

 

[Cory Cooper]

Great news and thanks for updating us.

So, can you now access the encrypted OS X partition?

C

 

[Blackhawk]

No, I reinstalled OS X, I could only save the windows data. I think I totally broke the old partition while trying to repair it^^