Hardware Reference
In-Depth Information
2. Once you have opened up Disk Utility, you will find your SD card on
the left-hand side in the list of devices. You need to right-click on every
partition in the list and select
Unmount
. This will stop the operating
system from using the partition. If you don't do this, you will get a
Device
in use
message when you actually write the image to the SD card.
