issue with xrdp

i cannot connect with my odoidc2 using xrdp. I have installed lxde and i can use it with a monitor on odroid c2. But if i try to connect from an other machine (win 7 machine) i have an error.
2018-01-20 18_26_24-192.168.1.2_3389 - Connessione Desktop remoto.png
2018-01-20 18_27_16-192.168.1.2_3389 - Connessione Desktop remoto.png