Incorrect DNS Settings Reappearing

I recently moved a virtualized server to a new host machine. In the process its virtual hardware changed, and so its MAC address changed. It got a new address from DHCP correctly and reported it to DNS, but DNS would only hold that information for about 15 minutes before switching back and reporting the old DNS.

After many frustrating hours I decided to check DHCP, and sure enough, DHCP had the old and new leases both with the same host name and was reporting them both to Active Direcotry.

Solution: Simply remove the old lease from DHCP, I'm sure eventualy it would have expired and fixed itself as well.