I'm trying to hook up my modem through my router.

You may want to have the modem working with your system first and hook up your router after wards.
Disconnect your router and modem.
Reboot your system.
Run your hard wire direct to your SB4220 from computer net card.
Allow to load whatever drivers necessary.
On your computer type ipconfig /all This will show you all your information.
Try the internet and see if it works. If you know the ip of your carrier, Type ping ????? ie: Ping comcast.net
If you recv. a timeout you still have problems.
If you succeed, you are their.

If not, type ipconfig /renew This will reset your ip and configurations.
Now, hook up your router and you should be their.