Didn't work =( same error message
The firmware upgrade was ok.
Everything else is ok, wifi speed it's better, less problems with Wifi.
Because my Yun was in contact with water, like I've said before, probably some part is damaged and is affecting AVR, USB/SD and SPI.
Thank you very much for your work with YUN. This Arduino was a bit abandoned until your contribution.
That makes me, and other people, trust and invest in this device for the future.