Got same problem. Lost all data and apps as unable to backup onto PC - hints and tips are useless unless properly described for laypeople. If you need to have advanced knowledge to understand them (e.g. “Geh in die Einstellungs App > über das Telefon und tappe 10 mal auf die Build-Nummer, damit die Entwickleroptionen erscheinen. Dann Einstellungen > Entwickleroptionen > USB-Konfiguration auswählen.”) you don’t need them in the first place.