Per What's a reliable method to create a stand alone recovery disk for Lion?, I'm attempting to create a two-partition thumbdrive such that one of the partitions is the Recovery Disk created by Recovery Disk Assistant and the other partition enables me to use the rest of the space for storage. Since I want this storage to be Windows 7/XP-compatible, its format will be MS-DOS(FAT).

So far, my attempts have been thwarted.

When booting my Mac with the thumbdrive inserted, I can select the drive but that only ever results in a gray screen. I have enabled FileVault 2 on this machine, if that matters.

What magic do I need to get a working external Recovery Disk on my thumbdrive?

Related: https://apple.stackexchange.com/questions/21303/two-partition-thumbdrive-unrecognized-under-boot-camp-windows-7


1 Answer 1


I have done this using the raw InstallESD.dmg image from the Mac App Store Lion installer (NOT the Recovery Disk Assistant) using the following steps:

  • Drag the InstallESD.dmg image to Disk Utility so that it appears on the side bar
  • Select your USB drive and partition the drive in to 2 or more GUID partitions
  • Once partitioning is complete, select the Restore tab
  • Drag that InstallESD.dmg image from the side bar to the source field
  • Drag the first partition from the USB drive on the side bar to the target field
  • Begin the restore process

Once finished you can leave things as they are or re-format the other partition as ExFAT or MS-DOS. However you should be aware the USB drive is GUID partitioned so only Windows 7 is likely to read it properly (I've never tried a GUID partioned USB drive on an XP system). You cannot use standard MBR partitions for the Lion Recovery Partition.

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