Last week I started having problems with my Mac (a mid-2010 Mac Pro running OS X El Captain), after searching for the cause I realized my OS X partition was corrupt.
A while back I turned on FileVault, and 2-3 weeks later all of a sudden my Mac started slowing down. In the end, 5 minutes after booting up my Mac simply froze, I wasn't able to do anything any more.
I decided to reinstall OS X but to my horror I realized that I couldn't select my original disk any more. No matter what I tried (I even booted up using a Windows 10 install disk to remove all the partitions on the disk) , I couldn't get OS X to reinstall on the same disk.
I finally gave up, installed it on the 2nd disk, installed Paragon Hard Disk Manager which allowed me to finally create a new partition on the disk, and started using it as a data disk.
I thought I had solved the problem, until I wanted to turn on encryption on the disk. I got an error message, which Google told me meant I didn't have an EFI partition on the disk.
So I googled around for a solution, found one but it made everything worse. Now even Paragon Hard Disk Manager can't create a working partition any more.
So... How do I clean up this mess? I have a working OS X install, I just want to create another partition on my other disk and encrypt it...
How can I fix this?
sudo gpt -r show disk1:
start size index contents 0 1 PMBR 1 1 Pri GPT header 2 32 Pri GPT table 34 2014 2048 1953519616 1 GPT part - EBD0A0A2-B9E5-4433-87C0-68B6B72699C7 1953521664 3471 1953525135 32 Sec GPT table 1953525167 1 Sec GPT header
When I first executed
diskutil list the list said there was a "Microsoft Basic Data" partition" on the disk. Probably the partition Paragon app tried to create:
/dev/disk1 (internal, physical): #: TYPE NAME SIZE IDENTIFIER 0: GUID_partition_scheme *1.0 TB disk1 1: Microsoft Basic Data 1.0 TB disk1s1
I'm not certain the disk isn't failing, but my current problem started after me trying to recreate the EFI partition, so I'm assuming it's still a logical problem rather than an actual hardware problem.