Become a MacRumors Supporter for $25/year with no ads, private forums, and more!


macrumors newbie
Original poster
Aug 8, 2011
Hi there

I wonder if anyone has any thoughts on this.

I have a new 27 inch imac, 10.8.3, 3.2ghz i5, 1TB spinning disk drive. I want to secure a few important documents so that in the unlikely event of theft or some sort of security threat, my most sensitive documents are under less risk of falling into the wrong hands. It probably amounts to 1gb or so.

What's the most sensible way to go about this without slowing down my entire machine? Can I just create a partition of 1gb sparse-image and encrypt it? (I tried this on my old MBP a few times and it failed due to all the resizing of existing partitions so I worry this process puts a lot of strain on my hardware).

I'd appreciate your thoughts.



macrumors G3
Jul 23, 2002
Sol III - Terra
Apple does not support encrypting disks with more than 1 partition with 2 exceptions. The first exception is the recovery partition and the second is a bootcamp partition.

There is no reason to not encrypt the whole disk. There is almost 0 performance hit. And many reasons to encrypt the whole disk. Did you have something confidential in email? Did your web browser cache something it shouldn't have that has too much personal info? Do you have PDFs of your financial statements on your computer?

Oh and another reason to encrypt the whole disk... less details to worry about with where do you put a file. And what if the amount of data ou need encrypted changes? I have my boot drive and my Time Machine drives encrypted.


macrumors 6502a
Feb 16, 2010
Have you tried TrueCrypt? TC will create an encrypted volume of any size on your drive. The TC volume will appear to the OS as a file.

TrueCrypt is free open source software for Windows, OSX, and Linux. If you format your TC volume as FAT32, it can be decrypted by TC on any of the three platforms.
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.