how to setup my new linksys re 6400 extender
To connect linksys extender to the network connect linksys extender  to the wall socket and press reset key for 30 seconds. Make sure it is close to the modem(maximum distance not more then 10 feet) Go to your computer or phone and open browser and type 192.168.1.1 in the top url bar. It will ask for your login information (default username and password is admin for both). Then it will open setup page. Just follow the instructions and your extender will get connect to the internet. Once it get configured you can connect any device with the network.