If you have a server with multiple NICs and if it is consisting to register it’s IP address to DNS server even while you uncheck the “register this connection’s addresses in DNS” option, I recommend you to create the registry entry below

Create a DWORD named  DisableDynamicUpdate under HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters and assign value 1 .

Or you can run the command below to easily create the record.

Normally this method shown for 2000 and 2003 servers in MS pages, but it is also working for 2008.