What if the Mywifiext.net setup is not working? You have to enter the web domain Mywifiext.net into the search bar of the browser and press enter. With the help of the authentication window that you see on your computer's screen, you can get the default web interface of your router. To access the default web-based interface of your router, enter the default username and password into the required field. Here, both the login credentials are admin. Netgear wifi extender setup using the WPS button is very simple.