Setup the Wi-Fi to Ethernet adapter

On your a computer, tablet or smartphone go to the Wi-Fi network settings and connect to the network "TP-Link_Extender"
Nb. On devices with a mobile data connection (ie. smartphones) it may be necessary to disable mobile data in order to access the adapter configuration web page. The WiFi Wi-Fi to Ethernet adapter won't have an Internet connection when it is first powered on, which may cause some devices to switch to a different network. You may need to force your device to stay on the selected network to configure the adapter.
Open a web browser on your the computer, tablet or smartphone and navigate to http://tplinkrepeater.net
Enter a new password that is in accordance with the customers network security policy, then click “Log In”.
Click on the Wi-Fi network you want to connect to.
Enter the password in the “Password” field then click “Next”, then click “Confirm”.
Click “Next” (To confirm the extended Wi-Fi network name), then click “Done”.

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With the Wi-Fi to Ethernet adapter powered on, use a small screw driver (or pen, pin, paper clip etc.) to press and hold the RESET button (small hole adjacent to the Ethernet port) until the entire ring of blue lights illuminate briefly (approximately 8 seconds).
Release the RESET button and wait the Wi-Fi to Ethernet adapter to reboot to its factory default settings.

Appendix: TP-Link user guide