Open CastHero on your TV first. It receives only while its screen is on the television, so a TV with the app closed cannot be reached from here. The TV's home screen shows its address, for example 192.168.2.16:8600. Your computer or phone must be on the same Wi‑Fi. Use Google Chrome: it asks once for permission to reach devices on your network, and the page needs that permission. Chromecast and Google TV via Google Cast use the Google Cast page instead; Roku is reached from the CastHero app.
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