Solution : https://service.sap.com/sap/support/notes/941405 (SAP Service marketplace login required)
Key words : 
prerequisites summarized jit calls, summarized jit calls, error message borgr 678 ', error message, transaction borgr, borgr transaction, terms borgr 678, handling units, sumjcs assigned, modification note
Related Notes : 
       
| 785211 | BORGR summarized JIT call + handling unit |