Furthermore, please be advised that there are models of Roku Express that are only compatible with wireless b/g/n networks on the 2.4 GHz spectrum. Ensure that your router is broadcasting a 2.4GHz Wi-Fi network for the device to connect to. You can check your device model by navigating to Settings > System > About.
You can also try configuring your router and use wireless channels 1, 6, or 11 which are the preferred channels in North America. Each time you change the wireless channel, you will likely need to apply/save changes before you are prompted to restart the router.
If you are powering your Roku by plugging into the USB port on the TV, try powering from house power via the USB power adapter that came with the Roku.
The ports on many televisions only supply 0.5 amp or less, which is not enough to power a Roku reliably. It may appear to start up okay, but when it runs into something that requires more power than the tv's USB port can provide, something's got to give. Frequently this results in shutting down the stream you are viewing and exiting back to the Roku home screen, or perhaps other problems depending on how bad the power shortfall is.
If this is a new problem, possibly an update to either the Roku operating software or to some channel app software is using a little more power than in the past, triggering this problem on a system that was barely creaking by before.
If you don't have a Roku adapter handy, any other you have from another device should work as long as the fine print on it says it outputs at least 1 amp.
Roku Community Streaming Expert I am not a Roku employee, only a user like you. Please, no support questions via private message -- post them publicly to the Community where others may benefit as well. If this post solves your problem please help others find this answer by clicking "Accept as Solution.".
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