What model Roku do you have?
Roku models Express, Express+, Premiere, and Premiere+ cannot connect to the 5 GHz wifi band, only to the 2.4 GHz band. If you have one of these models and a dual band router with both 2.4 and 5 GHz bands, be sure the router's 2.4 GHz band is turned on.
There have been numerous reports lately of people with ISP-provided routers having had their 2.4 GHz band disabled and having to have their ISP re-enable it.
If that's not the problem, try this:
- Restart your router (even if other devices have no problem finding and connecting). Sometimes that's all it takes, if not keep going.
- Restart the Roku to clear its memory via Settings > System > System restart (for a Roku TV it's Settings > System > Power > System restart). Again sometimes that's all it takes, if not keep going.
- Find and connect to your network via Settings> Network > Set up connection
If that doesn't fix it, try disconnecting the power to your Roku for a few seconds. When it comes back up, see if you then can set up the network connection.
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