Troubleshooting if you fail to use Chromecast on the Mi Smart Projector, please refer to the following steps:
1. Ensure your projector and casting device are on the same Wi-Fi network. Weak connections can cause Chromecast issues;
2. A quick restart might fix temporary issues. Turn off the projector, wait, and then turn it back on;
3. If Chromecast isn't working from a specific device, like a smartphone, try restarting it to refresh the connection;
4. Use the Google Home app to check for Chromecast updates. Install any available updates for better compatibility;
5. Make sure Chromecast is turned on in your projector's settings, usually found under Display or Connectivity;
6. If it stopped working suddenly, try disconnecting and reconnecting Chromecast to re-establish the connection;
7. As a last resort, perform a factory reset on Chromecast. Be aware as this erases all settings and data, so use it only if other steps fail;
8. If the issue persists, contact your local after-sales for further assistance regarding this issue.