This error message will be shown while you try to authorize your Adobe ID in the Onleihe App. It indicates a problem with Data remnants in the Onleihe App which prevent the authorisation.
This might also be due to some conflict with Your Adobe ID, which need not to be the users fault => Adobe ID

Please execute the following steps in the listed order, even if you did some of the steps already.

  1. Delete / deauthorise the Adobe ID in the App
  2. Delete the data in the onleihe app in the app manager
  3. Deinstall the Onleihe App
  4. Turn off your device for several minutes
  5. Install the Onleihe App
  6. Delete the data in the onleihe app in the app manager again
  7. Authorize your Adobe ID again, with the Adobe ID you used before
  8. Download and open your eBooks again