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 get the error message “Failed to add accessory”, put your iOS device in airplane mode for more than 30 seconds, turn airplane mode off again, and restart the installation. If you are using an Android device, make sure that no ad blocking apps are enabled on your device. If so, disable the ad blocking app when installing the Classe 300 EOS. If you want to install the Classe 300 EOS on a WiFi repeater: Make sure it doesn't have the same name (SSID) as the router. To check if the repeater is working properly, you can try installing the Classe 300 EOS directly on the router (by changing the network the smartphone is connected to as well).