Yamaha RX-V2600 message "start upgrader,,

[mitako3939]

Hello, I have a Yamaha RX-V2600 on which when I turn it on, the words "start upgrader" appear on the display. From the panel, not a single button works and it cannot be reset as described in the service menu. Nowhere in the service manual did I see such an error. Does anyone have an idea what to do? The description says that the UPDATING FIRMWARE program can be updated, but I can't find it on the official site or on the internet. If anyone has an update program or an idea how to program it to work again, please share. Thanks.