A solid-state storage subsystem, such as a non-volatile memory card or drive, includes a main memory area that is accessible via standard memory access commands (such as ATA commands), and a restricted memory area that is accessible only via one or more non-standard commands. The restricted memory area stores information used to control access to, and/or use of, information stored in the main memory area. As one example, the restricted area may store one or more identifiers, such as a unique subsystem identifier, needed to decrypt an executable or data file stored in the main memory area. A host software component is configured to retrieve the information from the subsystem's restricted memory area, and to use the information to control access to and/or use of the information in the main memory area.