SBS Networking Issues

I Have a SBS 2008 that was setup before I took over, we are in the process of changing ISP's  When I change the settings on the router to the new ISP Static I am unable to get out to the internet from the small business server or even ping public IP addresses.  If I go back to the old ISP on the router everything works fine.

Nothing has changed on the private network, on a workstation if I put in a public DNS server I am able to get out to the internet just fine if I put the DNS back to the small business server no joy.  Once I go back to the old ISP everything works fine.

I have rerun the fix my internet wizard with no luck.  I'm guessing someone ran the wizard in the beginning of the servers setup and did the router config and somewhere in the registry it is remembering the old router config even though that shouldn't matter.

The router still has the same private IP address so that hasn't changed it is just the public IP addresses that have changed.  If I configure a laptop with the public IP info on the new service I am able to get out on the internet just fine so it doesn't have anything to do with the new ISP.

Can anyone make any suggestions on what to try next short of calling Microsoft, let me know if you need any additional information.

Thanks

Todd