No internet on nt server

An NT server i have has lost the internet.
I have internet on all the other pc's in the building but not the server. Another two pc' seemed to be accessing the internet via the server and because the server cannot connect neither can these now.I have looked at the server settings and they are correct for DNS and gateway but cannot figure out why there is no internet.The network is ok but the router was recently reconfigured and replaced but this should not be the problem.
I am going to confiure the systems to access the server via dhcp and reconfigure the internet settings and hope that the pc picks up the internet.

Can you ping the gateway?

If so can you ping sites like www.yahoo.com and www.virtualdr.com ? (this is to isolate problems with the web browser itself, if you are using your web browser to test the "Internet")

I can ping the router ok. I am sure i have done this on the server but will have to double check next week.
If i can then i am not sure what to check.