Open the Home + Security app and select “Install new products” in Settings. Follow the instructions. Make sure your smartphone is connected to a 2.4 GHz network. The Classe 300 EOS is not compatible with 5 GHz networks. If you are using an iOS device and you are getting the “Unable to add accessory” error, put the iOS device in airplane mode for more than 30 seconds, remove airplane mode, and restart setup. If you are using an Android device, make sure that no ad blocking apps are enabled on the device in question. If so, please disable the ad blocking app when installing the Classe 300 EOS. If you want to install the Classe 300 EOS on a Wi-Fi repeater: Make sure it does not have the same name (SSID) as your router. To check if the repeater is working properly, try installing the Classe 300 EOS directly on the router (also changing the network the smartphone is connected to).