Help & troubleshooting for network issues, including connecting your device to your home Wi-Fi network, connecting to public networks, troubleshooting wireless issues & ethernet connections, and optimizing streaming performance.
First, the Express has a single band WiFi radio, so if your router is only broadcasting on 5 GHz, you need to enable the 2.4 GHz radio. The next thing is the channel number. The 2.4 GHz band has channels 1-14, but the top three are not permitted in North America so Roku devices will not see them. The best channels to use on 2.4 GHz is 1, 6 or 11. These are the only three channels that don't have overlap with each other. Most routers are set to auto-select the channel, so you may need to set it manually.
Dan Roku Stick (3600), Ultra (4640), Ultra (4670), Ultra (4800), Premiere (3920), Insignia 720p Roku TV, Sharp 4K Roku TV, Nvidia Shield, Windows 10 Pro x64 running Serviio and Plex on a wired Gigabit network.