Creating a EFI partition
I have been having trouble installing OS X Mavericks and I think I found the problem. It told me I couldn't boot up with Macintosh HD, so I verified my disk and I got this error: This disk doesn't contain an EFI system partition
So I figured out I can create one like this (tell me if I'm wrong): sudo gpt add -b 40 -i 1 -s 409600 -t C12A7328-F81F-11D2-BA4B-00A0C93EC93B disk0
from this question, but they also said the "index" must be 1, so I can't have anything at that index.
I ran diskutil list
and this is the output:
/dev/disk0
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *250.1 GB disk0
1: Apple_HFS Macintosh HD 233.0 GB disk0s1
2: Linux Swap 4.0 GB disk0s2
So I need to figure out how to move the indexes of Macintosh HD and that Linux Swap thing to indexes 2 and 3 instead of 1 and 2.
I don't know if this can be done without wiping and formatting my hard drive which I don't want to do, but if it can I would love to know how. Thanks!
By the way I'm on OS X mountain lion
Solution 1:
Usually EFI is on your Macintosh HD. It's likely still there, but not used due to messed up settings. This very easy to fix:
- Boot into a Recovery partition, DVD, or USB drive. Using the installation media that came with your device will suffice.
- Once loaded, you'll be presented an interface like:
- Close this window, and you'll be prompted to choose between
Startup disk
,Cancel
, andRestart
. - Select
Startup Disk
. The mere act of opening this utility with run the appropriate bless command in the background, repairing your EFI setup. - Select
Macintosh HD
- Restart
- Come back to Ask Different and up vote this successful answer :D