Does the SRT file have the same name as the movie? For example, if the movie is named "The Longest Yard.mp4" the SRT file should be named "The Longest Yard.srt" and be in the same folder as the movie. I assume you're using the Roku Media player, so if you're using some other app it would be nice to know. Of course, you also have to enable "Closed captions" either while the video is playing or using the Accessibility settings.
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