Abend S0C4 occurs when trying to save changes made to elements using the QUICK EDIT feature.
CCSR010E C1SSESTA S0C4 at 068C6388 LMOD ISPSUBS CSECT N/A +N/A SSPDKA1 SPFD SPFD
CCSR061I PSW: 00000000 00000000 078D1000 868C6388
CCSR062I ILC: 02 INTERRUPT CODE: 04
SYSTEM COMPLETION CODE=0C4 REASON CODE=00000004
If you hit the Help key, error message is displayed: "ENDI003S The dialog terminated with a S0C4 ABEND"
And the following message can be displayed when backing out of Endevor to ISPF: "IKJ56641I DYNASTEP ENDED DUE TO ERROR+"
Also the change in element should have been saved, you nedd to LOGOFF/LOGON ISPF.