Win2K DHCP errors

Do you have scopes with overlapping address ranges?

If you have a DHCP server in your networking environment and that server has scopes (range of possible IP addresses) with IP address ranges that overlap those of another DHCP server, IP addresses can't be leased from either server.

When scopes overlap, NAC (negative acknowledgement) entries appear in the event logs of both servers.

To check the event log for errors:

Click Start, point to Programs, point to Administrative Tools, and then click Event Viewer.

To resolve this issue, either remove one of the conflicting DHCP servers or configure the scopes so that there is no overlap.

To reconfigure an existing scope:

Click Start, point to Programs, point to Administrative Tools, and then click DHCP.

In the console tree, double-click the server whose scope you want to reconfigure.

Right-click the scope, and then click Properties.

On the General tab, change the IP address range to so that there is no overlap with other scopes.

If this doesn't help, can you give us any even IDs or errors you see in the logs?

Good luck!

http://support.microsoft.com/default.aspx?scid=kb;en-us;235979

Make sure the default servers are correct (according to the registry key defined in the MS link above) and make sure AssignNewClientsToServer is set to true.

Here are a couple of articles that may be helpful:

"Problems and Solutions of DHCP"

http://www.isoc.org/HMP/PAPER/127/html/paper.html

Did you just install RIS?

Microsoft Knowledge Base Article - 260536

http://support.microsoft.com/default.aspx?scid=KB;en-us;q260536

REMOVE SPACES from the pasted URL

You cannot have two main DHCP's on the same network. If you had you'd have unstoppable problems. You could configure them to share the tasks or disable either one of them.

You probably run your router as DHCP towards your server/firewall and Win2k server as DHCP towards the clients.

As I see it there's two possibilities why this happened:

1.) You moved/changed the router connections so it conflicts with the server

2.) Changed your router IOS so it tries to overrun your server DHCP
Here's a quote from an UNRELEASED MS article:

'This is a design feature of Microsoft Small Business Server. The DHCP
server service is automatically installed and configured when Small
Business Server is installed. To prevent the accidental installation of a
DHCP server on a network with an existing IP addressing scheme, the DHCP
server service is designed to shut down when another DHCP server is
detected on the network.'

This article will be released in the near future.

Hope this helps you :)

This question was closed by the author