The user data partition on the My Cloud is not encrypted. As far as I have seen when unbricking a My Cloud, none of the partitions of the My Cloud are encrypted.
When one mounts the My Cloud hard drive in a separate computer they will see several partitions. In the case of the v4.x firmware My Cloud’s the user data is located on partition #4 (for example in Linux: sdb4) which is formatted for EXT4.
