CompactFlash modules and cards are industrial- and research-grade storage media that are used with various Campbell Scientific peripherals and data loggers. These rugged modules and cards make data storage security, transportation, and mobility easier and more reliable.
The data logger should use the whole card, assuming there are no other CardOut() instructions in the program. Some options to try:
Ensure that a recent operating system is being used in the data logger.
Format the memory card in the data logger, which should ensure that the card is in a format the data logger fully understands. (Some PCs or card readers use obscure sector sizes, etc.)
When formatting the card in the data logger, use the File Control option in the PC software to check how much free space is reported in the card after formatting it.