Plug the laptop into the VMDG280 via ethernet cable temporarily to explore the settings in the modem. In
192.168.0.1 login with the user name & pass written on the side of the modem, Advanced Settings make sure its set to 2.4GHz mode and set to 54Mbps mode for B/G to eliminate the modem from the problem. Maybe you typed the key incorrectly, i use wpa2-psk(aes) with one password, thats all I can think of right now.