There is too much expanded storage. In ESA/390 mode, the maximum is 64 GB. In z/Architecture® mode, expanded storage is not needed and is not supported (the message shows a maximum of 0 GB).
Expanded storage reconfiguration is disabled, and the Display M command may produce unpredictable results. The system issues message IEE039A and continues its initialization process.
Contact the system programmer.
Reconfiguration.
IEERMAXW