FRITZ!Box reports "Connected the known powerline adapter [...]"
The message "Connected the known powerline adapter [MAC address]" is frequently displayed in the event log of the FRITZ!Box.
Not caused by an error
The message is displayed if the FRITZ!Box checked the connection to FRITZ!Powerline or another powerline adapter, and the connection was working correctly.
The message is therefore a normal status message; there is no error.