Windows 7 dhcp not updating dns
This might result in the client attempting to register an incorrect or unintended DNS domain name.
For example, the client might be attempting to register its short or unqualified computer or host name as a top-level domain name in the root zone.
If you are using other DNS servers on your network, verify that they are running a DNS server implementation that supports dynamic updates.
For more information, see Understanding Dynamic Update.
For example, if the client computer obtains its IP address lease from a DHCP server, you might use the ipconfig /renew command to force the client to renew its lease with the DHCP server.
This action then causes the DHCP server to submit an update request to its configured DNS server on behalf of the client.
If the DHCP server succeeds in performing the update with the DNS server, the result is an updated DNS host name and updated IP address information for the client computer in the DNS database.
Cause: The client was not able to register and update with the DNS server because of missing or incomplete DNS configuration.