The /dev/disk1 is a virtual disk created because of the partition encryption ( FileVault 2) I enabled in Mac OS X.

dev/disk0ģ: Apple_Boot Recovery HD 650.0 MB disk0s3ġ: Microsoft Basic Data UNTITLED 1 2.0 GB disk2s1Īs shown in the output above, the connected USB stick is a small 2.0 GB drive with a FAT partition on it. We are now going to remove this partition in the next step. With the following command the data on the disk (your USB stick) will be deleted! $ diskutil partitionDisk /dev/disk2 1 'Free Space' 'unused' '100%' For the following steps we will need the name of the disk which in this case is “/dev/disk2”. With this command the USB stick was re-partitioned to have 1 partition without formatting and 100% of the size of the stick.

If you check it again with “diskutil list” you will see the changes already, also the USB stick will no longer be shown in the Finder. This command will copy the image to the disk (substitute the appropriate disk name for your USB stick here, as with the re-partitioning command): $ dd if=destination_ of=/dev/disk2 bs=1m Now we can copy the disk image we created to the USB stick.

The dd command does not show any output before it has finished the copy process, so be patient and wait for it to complete. To eject the USB stick, use the above command.

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