Switch Windows 8 from a hybrid MBR/GPT => GPT only on Macbook Pro Retina
- by Sid
I used DiskUtility+Bootcamp Wizard to setup my hard drive for Windows 8 (final MSDN). Somewhere in that process, the Apple tools turned my GPT disk into a hybrid MBR/GPT. All my 4 primary MBR partitions are used up, so when I try turning on Bitlocker in Windows 8, it complains about not finding a System drive. I know on Windows 8 the Bitlocker setup tries to create the 200(?)MB system partition if it's missing. However with all 4 partitions filled I suspect it can't create system drive = it can't find it = throws back an error like "BitLocker Setup could not find a target system drive. You may need to manually prepare your drive for BitLocker". I've already tried disabling hibernation, swap file etc. Now I'm thinking that if I were to get rid of the MBR scheme altogether, perhaps I can be alright within the GPT world without MBR's 4 primary partitions limit.
So, how can I get rid of the MBR tables on the hybrid scheme in a manner that still leaves Mac OS and Windows 8 in working conditions?
Details:
Hardware is the MacbookPro Retina. Primary MBR partitions are consumed as follows:
EFI partition
HFS+ partition (=encrypted, therefore ="Apple_CoreStorage")
HFS+ partition (Recovery partition, contains unencrypted Mac bootloader)
NTFS partition (Windows8 all-in-one partition)
diskutil list output
sid-mbpr:~ sid$ diskutil list
/dev/disk0
#: TYPE NAME SIZE IDENTIFIER
0: GUID_partition_scheme *251.0 GB disk0
1: EFI 209.7 MB disk0s1
2: Apple_CoreStorage 160.0 GB disk0s2
3: Apple_Boot Recovery HD 650.0 MB disk0s3
4: Microsoft Basic Data Win8 90.1 GB disk0s4
GPT vs MBR addresses
sid-mbpr:~ sid$ sudo gptsync /dev/rdisk0
Password:
Current GPT partition table:
# Start LBA End LBA Type
1 40 409639 EFI System (FAT)
2 409640 312909639 Unknown
3 312909640 314179175 Mac OS X Boot
4 314179584 490233855 Basic Data
Current MBR partition table:
# A Start LBA End LBA Type
1 1 409639 ee EFI Protective
2 409640 312909639 ac Apple RAID
3 312909640 314179175 ab Mac OS X Boot
4 * 314179584 490233855 07 NTFS/HPFS
Status: GPT partition of type 'Unknown' found, will not touch this disk.**
**: Ignore this message, the gptsync tool is old and doesn't understand the UUID for "Apple_CoreStorage" / FileVault2 partitions. Since LBA addresses are alright, safe to ignore this message.