If you haven't got a user guide you can download one in PDF format from click here. According to this you can access the setup for the router by typing 192.168.1.1 into the address bar of your browser. To get into the administrative web configurator you should type in the username "user" and the password "1234" but without the quotes and then click "Login". Once into the setup you should click on Network > Wireless Lan and then on the AP tab remove the tick from "Active Wireless LAN". Click "Apply" and exit from the setup.