I recently changed my WiFi router and Roku Express will not accept the new SSID/password. I did a reset and my previous Wifi SSID is still locked in.
The only screen I can get to is the select language screen. I have reset my modem, router and Roku device multiple times.
I have successfully used the SSID/password on other electronic devices.
I don't know what the problem could be with your Roku, but you could try changing your SSID and password to what they were with your old router.