Abstract: An apparatus and a method for storing diagnostic software on a data storage device provides one or more ghost partitions overlapping a user partition on a data storage device. During a factory download of the application software as well as the diagnostics software, the apparatus creates a user partition and one or more overlapping ghost partitions. Next, it determines a minimum and maximum partition size for the ghost partition(s) and allocates the ghost partition size(s) appropriately. The apparatus then creates one or more master boot records (MBRs), one for each created partition. The ghost partition containing the diagnostics software is set as the active partition to allow the diagnostic software to be executed. Upon completion of the diagnostics process, the MBR for a second ghost partition is enabled so that upon reboot, download verification software located on a second ghost partition can be executed to ensure the correctness of the software downloading process.