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I have a new 16Gb USB key and want to take advantage of Disk Utilities feature to encrypt it, however I do need to move data from Mac to Windows from time to time.

Is is it possible to have one FAT partition and one Mac OS Extended Encrypted Partition on a 16Gb drive? I've tried a number of times but cannot figure it out.


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Yes. It's pretty straight forward, to do so just:

  1. Go to Applications / Utilities / Disk Utilities.
  2. Select the USB device and click Partitions.
  3. Choose the number of partitions you want and resize them as needed.
  4. Choose the format of each partition and click *Apply.
  5. Once mounted on the Finder, Control+Click the Mac OS Extended partition and choose Encrypt.
  6. You'll be prompted to choose a password. Enter it and click Encrypt Disk.
  7. Wait. Unfortunately, there is no progress bar, so you won't know exactly how long will it take. I just did it with a 4 GB USB drive and it took from 5 to 10 minutes.

And it is done.

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Hey, I had already tried that before asking and it failed. "The given file system is not supported on Core Storage". I also made sure my my partition scheme is GUID. – Touff Oct 15 '12 at 11:49
You can monitor the progress by calling "diskutil cs list" on the command line: Conversion Progress: 0% – ocroquette Nov 17 '15 at 19:56
up vote 0 down vote accepted

Ok I found this thread hidden away in the Apple communities and it provided the solution. I was trying to do it through the Finder, I went back and tried it again using Disk Utility and it worked. Strange...

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