Ok so I had two express Roku's both of which received the latest update and stopped connecting to any wifi network. All other devices in my house are still working fine. I reset my router, did a network reset on the devices, finally followed by a factory reset on each. One device will not see any networks at all, the other still sees them but will not connect. Also will not connect to my phone or tablet hotspots which they used to work as well. Also on my router it does not see either devices mac address broadcasting. Went out and bought an ultra and it works just fine. This is the third time in 10 years Ive had to upgrade because an update killed my devices. Seeing as the express still sells I don't understand why Roku would do this but this will be the last product I buy due to thier "planned" obsolescence
Roku Express/Express+ (prior to the new Express 4K) and Premiere/Premiere+ are lower end units with single band Wi-Fi radios that only support the 2.4 GHz band. They, and many other devices of all sorts that are 2.4 GHz only, can't even see the 5 GHz band, let alone connect to it. If you have one of these models and also a dual band router with both 2.4 and 5 GHz bands, be sure the router's 2.4 GHz band is turned on.
[Note, there have been a number of reports lately of people who have routers supplied by their Internet Provider in which the router's 2.4 GHz band was disabled by an update to the router software. They've had to have their Internet Provider re-enable the 2.4 GHz band, or in some cases swap in a new router with 2.4 GHz support.]
Within the 2.4 GHz band, Rokus use channels 1 through 11 as are used in North America. Some other parts of the world also support channels 12 & 13, but Rokus can't even see these channels. Be sure your router is set to only use channels 1 through 11. If your router supports these higher channels and also has an auto channel selection feature that may switch to one of them, make sure this is not configured.
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