My Buffalo Airstation Won't Connect To The Internet?

It may be worth doing a power cycle -
If that does not help - resetting the router back to factory settings and reconfigure
How to power cycle:
"power cycle" process to reboot or reset the modem/router
1. Switch off all the devices modem router and computers also unplug their power cables.
2. Wait at least 1 to 5 minutes.
3. Plug the power cords back in but don't switch them on.
4. First turn on the modem and then wait for a few minutes for it to settle and all the lights to become stable.
5. Next switch on the router (if a seperate device) and then wait for a few minutes for it to settle and all the lights to become stable.
6. Now turn on your computer You should now be able to access the Internet.