I have a #Roku Express 4+ device that has stopped working. The "on" blue light in the device is on. The remote control will turn on and off the Samsung, along with adjusting the volume. I will select the HDMI source it is connected to and doesn't register on the tv. I have tried unplugging it and plugging it in, tried it on different TVs, and pushed the reset button. The device is about a year old.
Have you tried another HDMI cable? Beyond that about all that's left is a factory reset. Using a paperclip or something similar press and hold the reset button with the power connected for no less than 30 seconds.
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