Message Class list used by SAP ABAP Class CL_ISU_INSTGR_SCHED_DATA (Schedule Records at Installation Groups)
SAP ABAP Class CL_ISU_INSTGR_SCHED_DATA (Schedule Records at Installation Groups) is using
# Object Type Object Name Object Description Note
     
1 Message Class  AH IS-U billing (master data)
2 Message Class  E9 General IS-U Error Messages