Working from the wiki section "Begin Product Customization" (see link below), when I try:
TSO EX DATACOM.MFAPPTNRCEESCLS0(TRCUST)
I am getting:
DATA SET DATACOM.MFAPPTNR.CEESCLS0.CLIST NOT IN CATALOG OR CATALOG CAN NOT BE ACCESSED
Why is the CLIST trying to find that dataset?
As entered, the TSO EXECUTE command was incomplete; the required parameter PREFIX(&hlq) was missing.
Please note that the full command is
EX '&hlq.CEESCLS0(TRCUST)' 'PREFIX(&hlq)'
Refer to the Begin Product Customization steps found in the CA Mainframe Application Tuner documentation wiki: