I am replacing my old Airport Extreme V5.7 with a newer one V7.5.2. I have plugged the newer one properly into my router and reconfigured it. My computers recognize it fine, but the internet doesn't work. It's like the router won't talk to the Airport.

I am replacing my old Airport Extreme V5.7 with a newer one V7.5.2. The old Airport Extreme works, but I had to restart it once or twice a day, so I thought I'd hook up the newer one. Like the older one, the newer Airport Extreme was used in the U.S. and worked just fine there. Now I am in New Zealand trying to hookup the newer Airport Extreme. I have plugged the newer one properly into my router and reconfigured it to make sure it is up to date. My firmware is up to date. My computers recognize the new Airport Extreme and the newly named network just fine, but the internet doesn't work. It's like the router won't talk to the Airport Extreme, even though the router cable is properly plugged into the Airport. I cannot solve the problem. Please help. Thank you.