I have not found a clear explanation of factors affecting Secure Dynamic Updates, specifically regarding a potential user account for updating DNS and the relationship to DHCP. I have a network of Windows 2003, SP2 servers. DNS is AD Integrated. There are 4 locations with Domain Controllers/servers.. Location 1: 2 Domain Controllers, both with DNS, one DC is also the DHCP server for the location. Location2: 1 DC with DNS and DHCP. Locations 3 and 4: 1 DC each with DNS. Sites are small and static IP addressing is used. All DNS servers are Primary, pointing only to themseleves, forwards are the ISP's DNS servers. Currently Dynamic Updates are "Secure and Non-secure". I want to change to "Secure Only" but the uncertainty about an user account and how it relates to DNS and DHCP has held me back. I can find no clear explanation of this anywhere. DNS works fine, its the Secure ONly issue that needs addressing. thanks dave Admin