Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

brownamazingnes

macrumors newbie
Original poster
Aug 6, 2013
1
0
Today, I rebooted my 2009 Macbook Pro and I tried to bootcamp, when it said "The startup disk must be formatted as a single Mac OS Extended (Journaled) volume or already partitioned by Boot Camp Assistant for installing Windows." I went to disk utility to see if there was a problem, so I verified the disk. When I verified the disk, it said there was a problem in my partition map and "This disk doesn’t contain an EFI system partition. If you want to start up your computer with this disk or include it in a RAID set, back up your data and partition this disk."
 
If you want to start up your computer with this disk or include it in a RAID set, back up your data and partition this disk."

Make sure you backup your data before anything else.
Can you show us you current partition table using "diskutil list" in the terminal, for example:
Code:
$ diskutil list
/dev/disk0
   #:                       TYPE NAME                    SIZE       IDENTIFIER
   0:      GUID_partition_scheme                        *500.1 GB   disk0
   1:                        EFI                         209.7 MB   disk0s1
   2:                  Apple_HFS Macintosh HD            480.0 GB   disk0s2
   3:                 Apple_Boot Recovery HD             650.0 MB   disk0s3
   4:                  Apple_HFS newVolume               8.0 GB     disk0s4

The partition type "EFI" is the EFI system partition, but there might be something wrong in your case. Your one will be a little bit different if you have attempted to install bootcamp.

This thread on stackexchange might help:
http://apple.stackexchange.com/questions/57597/how-to-fix-broken-efi-partition
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.