I recently received a Flex streaming device when I subscribed to Xfinity Internet service. The Flex box worked fine when the installer first configured it to connect via WiFi to the Xfinity-supplied Gateway. I have since purchased a Motorola MB8600 cable modem to replace the Xfinity Gateway. I have the MB8600 feeding a Gigabit Ethernet router, which provides DHCP, NAT, etc. for a wired Ethernet network that runs throughout my house. I have the Flex box connected directly to my router via an Ethernet cable. Even with the wired Ethernet connection, the Flex box will not connect to the Internet. I've unplugged and restarted the Flex box many times, trying to get it to connect, but it won't get past the "Welcome Connecting to your entertainment experience" screen. It eventually lands on a error screen with error code RDK-03117. When I check my local network map, using my router's management GUI, the Flex box MAC address does not appear in the list of connected devices. This leads me to believe the Flex box is not joining my local network to begin with, so I can't even ping it, let alone connect it to the Internet. BTW, I also tried to connect the Flex box via WiFi to my in-home Access Point, but I got no further than I did with the wired Ethernet conection. Any suggestions for troubleshooting would be much appreciated.
Thanks for your suggestion. Yes, the Flex box had been working with the Xfinity Gateway (i.e., WiFi Router/Cable Modem combination). But I can't get it to work with my WiFi Access Point. Using WPS to connect the Flex box to my AP does not work. Manually entering my WiFi SSID and password doesn't work either. The Flex box "sees" my AP SSID, but it still fails to connect to the Internet, and its MAC address still does not show up in my AP's network map (like all my other wireless devices do). And WiFi has nothing to do with the fact that the Flex box won't connect to the Internet, even when I connect it directly to my router with a wired ethernet connection. And its MAC address still doesn't show up in my router's network map.
It is definitly not connecting to your new modem. There is, as far as I know no WPS button on the Motorola Modem. (Mine is old). I f you have it hard wired to your wifi router, then try setting the WPS on the router and the Flex box at the same time. I had to do this with my Flex when it arrived a few days ago. Unplug for a minute, plug in,when it starts looking to connect, press the WPS button, then run to the router and press it's WPS button.. Like I said, only way I got mine to connect.. Good Luck