Are Netflix and Roku Channel the only two affected channels/apps you are having an issue with?
The 003 error (update error) is usually an internet error message since the update server is unreachable. (Roku is not detecting an internet connection).
If you are able to stream from other channels/apps with the Roku device then the Roku device is clearly connected to internet and the Roku servers (or at least the servers being used for Roku Channel and Netflix) are not detecting an internet connection or do not like how you are trying to access the server.
Need to determine if the Roku device is actually connecting to the internet (versus merely connecting to the network). Try connecting the Roku device to a mobile hotspot (if available to you) and see if you can connect and stream. If so, then need to look at a router/network setting.
Feel free to post back with router model number and ISP (internet service provider). The culprit could be anything from using an incompatible wireless channel, having a setting that is blocking the MAC address of your device, a setting in an ISP app that is inadvertently "paused", to having a password issue.
Providing the router model number will at least tell us what settings to look for to make some recommendations to you.
Roku Community Streaming Expert
Just another Roku user... I am not a Roku employee.
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