I recently changed the internal IP addresses of 3 Windows 2008 servers. Now one of the old IP addresses (10.10.15.21) is refusing to be assigned to a new computer (no problems with the other 2 which were .25 and .26).
Windows 7 claims that the IP address is in use by a device on the network (even though the server originally using that IP had no problem using it for a number of years). The event log entry says there is conflict for IP address 0.0.0.0 on the hardware address 00-00-00-00-00-00 which is not very helpful at all.
I have tried ping scans of the network which show that the IP address in question is not responding and the address does not show up in arp tables. I am now at my wits end and looking for advice on what to do next.