HDMI out from laptop will not duplicate display, only extend as a second monitor
Two days ago our Roku TV would duplicate my laptop screen just fine, but now it can only extend the display as if the Roku TV is acting as a second monitor to my laptop. I have tried changing HDMI cables 3 times now, gone through most my computer settings down to even checking if it was a problem with my Windows Registry Editor. All signs ended up pointing back to the Roku TV as changing my Windows laptop has done nothing so far to fix the problem. I have also already tried hitting the Windows key + P and selecting duplicate from the list, but even though I can select it, it reverts back to extend.
Re: HDMI out from laptop will not duplicate display, only extend as a second monitor
If you search the Internet for "windows can't duplicate display" you'll find plenty of people with the same issue you're describing going back years. I don't think it's the TV, although I did find one person that had to turn off "theater mode" on his Sony TV to get his display to duplicate, so I suppose it's possible that there's a TV setting that affects it.
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