Clients not registering DNS

[OutLawTorn]

During the recent school holidays we changed our IP address range from an internal range (172.16.0.0/16) to a NSW (Australia) Department of Education and Training range (10.18.144.0/22). The servers were rolled over, and then the DHCP range updated to match (including dns servers and the like). However now we're having a problem where DNS aliases set on our internal server are not being identified by the workstations.

They get a correct IP address from the pool, and the correct DNS server details in the configuration, however will not resolve internal dns aliases unless you run "ipconfig /registerdns".

While we can run this as a logon script, once the PC has been on for a while the workstations go back to not resolving the addresses unless you run the "ipconfig /registerdns" again.

Any ideas?

[SYNACK]

Did you remember to add a new Reverse lookup zone in DNS for your new subnet when you changed over as this can sometimes get in the way of registration.

The other thing that I would check is to make sure that there are DNS dynamic update credentials set up in your DHCP servers properties page under advanced. This ore make sure that all users and computers in the domain have permission to update their records.