Is this express brand new out of a box or just new to you? Does the roku remote have a tv power button and volume keys the side? It shouldn't, express comes with IR remotes it should just work by pointing at the front of the express. You do have line of sight to the roku? You can check to see if the remote is emitting a signal by pointing at the cell phone camera, if you see flashes its working, then it might be the express itself?
Edmund
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