Hello @Clere ,

Here are some steps to help you:
1. Ensure your device is connected to the Range Extender's Wi-Fi network.
2. Try using the IP address of the Range Extender instead of the domain name.
3. Reset the Range Extender to factory default settings and set it up again.
4. First-time login: If this is your first time signing in, you will be prompted to create a password to manage your extender. If you are asked for a username and password, please try using 'admin' for both fields.