EX7000 won't connect to network

I can connect my laptop to the wifi extender (the EX7000) -- the status light shows it -- and I can navigate the web via my extender's network, but I cannot access the extender itself via mywifiext (at net or local). I want to get into its settings to secure it, etc. My router is a CenturyLinke Greenwave C4000XG. Appreciate any thoughts.