I configured a new IP address with the DHCP binding to it and then switched back to the old IP and the problem was fixed.
I had this when Microsoft WDS was installed on the same server. WDS can claim the same Port and this prevents DHCP from creating a binding to the Adapter. Stopping Windows Deployment Services allows the binding to be remade.
This event occurs because of a bad NIC, incorrect NIC hardware settings or incorrect TCP/IP settings.
This problem can also appear if the DHCP service and the ADS PXE service are both installed and running on the same server. See the link to "Configuring ADS Services" for information on fixing this problem.
If you use a Dell server, do not install the Dell OpenManage software on the server. It binds to the port when booting the computer and therefore the DHCP server cannot bind to it. You can check this by running “netstat -a -n –o” to find the process that is grabbing port 67 (DHCP Server) and then uninstall that program from the server.
As per Microsoft: "This behavior can occur because the DHCP server service is not bound to a statically-configured Transmission Control Protocol/Internet Protocol (TCP/IP) adapter, which is usually the internal adapter". See ME298490
for more details.