One other possibility.
In the 2.4 GHz band, Rokus support connecting via channels 1 through 11, as are used in North America. Some routers may also support channels 12, 13, and (I think) 14 as are used in some other geographical areas.
If your modem is using a channel above 11 (or an auto selection setting that could assign a channel above 11) your Roku won't be able to see your network.
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