Why does Chromecast not connect with my desktop PC? It’s a Gateway SX2802 running Windows 7 Home Premium connected to the internet via a wired connection to a DSL broadband router. The error message is “your Wi-Fi is off” “Wi-Fi needs to be turned on for the Chromecast App to work.” The wi-fi is on and I’m able to connect with my tablets, laptop and phone. I hope you can help me now. Thanks.