Chromecast devices are optimized to work best with specific Wi-Fi standards depending on where they are sold. This means if you buy it in one country, it may not work as expected, or may not work at all, if you try to use it in a different country than where it was purchased (so long story short is it depends what country the Chromecast is designed for). The first thing to try is to factory reset your Chromecast and retry setup. If that doesn’t resolve the issue, there are some workarounds you can try:
- If your router is a dual band router and has different network names for the two Wifi bands, make sure your phone and the Chromecast are connecting to the same Wi-Fi band (2.4GHz or 5GHz).
- Login to the admin page of your router (refer to the manual or the back of the device).
- Navigate to Wifi or Wireless settings (the naming of the menu options you see will differ by router manufacturer and you may need to click to go into "advanced" settings to see some options).
- If your router is a dual band router and doesn't currently have different names for the two bands, look for an option to turn on different network names for the two bands.
- If "Wifi Protected Setup" or "WPS" is enabled, disable it.
