That means you either change the tg1672 to a modem only (find its manual) or configure your *Tenda router to be a WAP. Here's the google I use for that.
"How to use a router as a WAP?"
Note: Edited by moderator to correct spelling.
i have a tenda wireless router model #w268r that was working fine with my old modem (time warner service)
the cable company gave me a new modem (arris #tg1672) and now the wireless router does not connect. my wireless laptop still sees the network name and says its connected but gets no internet connection at all
the new modem arris #tg1672 has 4 yellow output ports,
one is used to connect direct to my desktop and the internet works fine, the other is used to connect to the router which is not responding. (running windows 7)
any help will be appreciated