 USB cable:
1. Phone must be powered on.
2. Type ##634#, then type *#7284# and choose "QC RmNetComposite" option.
3. Apply confirmation and wait till phone reboot.
4. Connect USB cable, install drivers if needed.
5. Select diagnostic port in port settings.
6. Press "Read QCN" button to read NV backup or "Write QCN" to restore.