Solution : https://service.sap.com/sap/support/notes/563148 (SAP Service marketplace login required)
Key words :
0b import support package 28, 1c import support package 20, message appears indicating, message brain 818 reason, 0b support package 28, 1c support package 20, a__b navigation attribute, bw support packages, support package, navigation attribute
Related Notes :
| 523186 | SAPBWNews BW 2.1C Support Package 20 |