The best way to avoid these errors is to not eject the volumes in the first place. If this is not practical, then the tape volume record should be kept by using the KEEP option of the LIBRARY EJECT operator command or through the ISMF Mountable Tape Volume line operator when the volume is ejected. This preserves the information about the tape volume so that the Cartridge Entry Installation Exit does not have to rebuild the tape volume record.
If a job on a lower-level system inadvertently requests a volume whose media type or recording technology is not understood at this software level, the exit can cancel the job, returning a return code 8, or it can proceed with entering the volume. If the exit proceeds and enters the volume, once it is successfully entered on an up-level system and the exit returns with a return code 4 (indicating retry), the job on the down-level system fails during job step setup on subsequent retrieval of the volume record. If the host detects that it is an up-level volume (if the TCDB volume record exists), the call to the exit is bypassed and the job is canceled.