Internet on domain server, none on client machines

I have a domain network where the two domain servers are able to get internet connectivity but none of the client computers are able to get internet connectivity. Everything was working up until we installed IIS so that we could install Symantec End Point. After that all internet on the client computers, all 47 of them, went out. I am still able to get online on the server but no where else… After all of this, then we started having roaming profile problems where the cleint computers couldn’t find the server profile…. I think I’m getting in over my head and need help!!!!