Wireless Network troubleshooting Netgear AX1800 router
I'm having issues connecting to my wifi. My Roku is a Roku Express (3930, 3931 series) # I'm using a Netgear AX1800 router. For my phone, I had to change the wifi settings to use the device's MAC address. It sees the network, but when I enter the password it will not connect. None of the stages have a checkmark when it fails.
The Roku Express 3930 is only 2.4ghz capable. (It cannot see or use the the 5ghz band).
Try changing your "Wireless Security" from WPA3 to WPA2-Personal in the AX1800. Then restart both the Roku device and the router. If it connects successfully, you can then try using WPA2/WPA3 in the settings and see if still able to connect.
Roku devices cannot currently connect if a router (like wifi6 AX) is set to WPA3-only.
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As for the g/n and b/g/n setting under "Wireless Mode" on the 2.4ghz band, this is not a universal issue and pertains mainly to leased cable ISP routers or routers purchased with cable ISP firmware. Roku devices should be able to connect to routers configured with g/n, but a good troubleshooting step would be to use the default b/g/n setting as mentioned by Anonymous if having issues connecting or remaining connected to a network.