Currently have Windows 2008 R2 server with DC,DHCP and DNS configured. Currently using Qwest DSL internet service with ActionTec modem/router. Attempting to switch to new Mediacom Business internet service with Cisco WRVS440N router. Qwest and Mediacom DNS Forwarders are entered in DNS on server and resolve correctly when connected to ActionTec. Both routers are configured to same IP because we have static IP's on numerous workstations. Only have one router connected at a time. When new router is connected cannot ping router or resolve DNS addresses in Forwarders screen. If I go to a workstation and replace DNS address for Domain server to ISP's DNS servers I can browse internet. Seems to be DNS issue with Windows 2008 R2. Appreciate you suggestions.