To the knowledge base

FRITZ!Powerline reports "Authentication error occurred" when using Google calendar

The error message "Authentication error occurred" is displayed for the Google calendar on the tab "Switch Automatically" in the "Smart Home" menu in the profile of your smart home device in the user interface of the FRITZ!Powerline adapter.


  • The FRITZ!Powerline adapter's access rights to the calendar were revoked in the Google account.

1 Deleting a calendar

To request access rights for the calendar again, you must first delete all of the Google calendars in the FRITZ!Powerline adapter:

  1. Click "Smart Home" in the FRITZ!Powerline user interface.
  2. Click the (Edit) button for the respective device.
  3. Click on the "Switch automatically" tab.
  4. Click the link "Remove connections from Google calendar".
  5. Click the "Reset Google Calendar" button.
  6. Click "OK" when you are asked whether you want to delete all Google calendars from the FRITZ!Powerline adapter.

2 Adding a calendar