If you are not located in the US, or another country that Hulu supports on the Roku, it won't install. Roku does not control where channels are available. Only the channel provider controls that.
If you are not in the US, and Hulu is available in your country, it's possible that Hulu hasn't made their service available on Roku devices. Again, that's not under Roku's control.
If you are in the US, then my next question is if you're using a VPN on your network. VPN use will mess with many channels on Roku devices.
Dan
Roku Community Streaming Expert
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