Solution : https://service.sap.com/sap/support/notes/1332367 (SAP Service marketplace login required)
Key words :
symptom error message 8w 289, attached correction instructions, md04 /afs/md04, program error, afs materials, terms retpo, purchase order, item indicator, ekpo-retpo, 161 movement type
Related Notes :
| 1458523 | No error message issued while saving Return Purchase order |
| 934129 | FAQ's on AFS-Purchasing |
| 503098 | Returns items in the purchase order |