Import failure when trying to import decks

Hi everyone!
Sorry for my bad English, I’m from Germany.
I am unable to import decks. The following message occurs:

Import failed. Debugging Info:
Traceback (most recent call last):
File “aqt/importing.py”, line 404, in on_done
File “concurrent/futures/_base.py”, line 432, in result
File “concurrent/futures/_base.py”, line 388, in __get_result
File “concurrent/futures/thread.py”, line 57, in run
File “anki/importing/apkg.py”, line 37, in run
UnicodeDecodeError: ‘utf-8’ codec can’t decode byte 0xb5 in position 1: invalid start byte

I already deactivated the add-ons and updated to the newest version of Anki. Maybe someone can help out?

If it failed even with add-ons disabled, please check that you haven’t enabled the legacy importer in the preferences screen.