Solution : https://service.sap.com/sap/support/notes/1088209 (SAP Service marketplace login required)
Key words :
GUI_DOWNLOAD, GUI_UPLOAD, garbled characters, character encoding
Related Notes :
| 1319517 | Unicode Collection Note |
| 1073779 | setting the Frontend Up-/Download Codepage |
| 765763 | Setting the Upload/Download codepage for a SAPGUI connection |