Xp clients not updating dns via dhcp

The dynamic update GPO controls this behaviour on a per-computer basis; when it is disabled, the per-connection "register this connection's address in DNS" option has no effect and dynamic registration does not occur, leaving the DHCP server to take care of it without interference.You should set this GPO only on computers which should be DHCP clients.

Each DHCP server has the 'DNS dynamic updates registration credentials' setting populated with a user account which is a member of the 'Dns Update Proxy' group, and (although I've seen arguments for and against) I've added the servers themselves to the 'Dns Update Proxy' group.

The DHCP servers are configured with the following settings ticked: 'Enable DNS dynamic updates according to the settings below' 'Always dynamically update DNS A and PTR records' 'Discard A and PTR records when a lease is deleted' Some PCs seem to work fine.

When a client unregisters, the record is marked as dns Tombstoned.

The record still exists, but is not visible in DNS Manager.

They request a DHCP address, and the DHCP server hands them one and updates DNS.