|Don't run internet thru the server. Use the router.|
Correct dhcp setup:
enable and authorize dhcp from the server
disable dhcp from the router.
in the dhcp server scope set the ip address of the server for dns
gateway is the router ip
Correct MS DNS setup:
Go to the forwarders tab [not to be confused with forward lookup zone]
and input the isp's dns server ips.
Sonicwall [and others] make firewall routers that support subscription services. For example our sonicwalls have antispam and antivirus/malware subscriptions that stops the bad guys at the firewall.
It is still wise to have AV/Antimalware/windows software firewall engaged on the pcs and server.
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