Microsoft KB Archive/166854

{| = WinNT 4.0 SP2 DHCP Server NACKs Requests If No Address Available =
 * width="100%"|

Article ID: Q166854

The information in this article applies to:
 * Microsoft Windows NT Server version 4.0

SYMPTOMS
Windows NT 4.0 Service Pack 2 (SP2) DHCP servers will NACK a DHCPREQUEST for other DHCP servers when they have given out all available addresses. You may receive the following error message on your client when running the IPCONFIG /RENEW command:

Access Denied - Renewing Adapter "xxxx" In addition to the above error message, you may receive the following eventlog messages:

On the Client
Event ID: 1006 Source: Dhcp Type: Warning Category: None Description: DHCP service is shutting down. The following error occurred: Access is denied.

On the Server
Event ID: 1011 Source: DhcpServer Type: Warning Category: None Description: The DHCP server issued a NACK to the client (MAC Address of               the Requesting Client) for the address (Requested IP                Address) request.

CAUSE
This NACK happens when you have multiple DHCP servers and one of the DHCP servers with Service Pack 2 runs out of available addresses. If the server gives out all the available addresses, and then receives a DHCPREQUEST from the offer of another server on the same segment, it will NACK the request.

NOTE: This may be an intermittently occurring problem, and will not show up if the second server responds before the SP2 DHCP Server.

RESOLUTION
Obtain the latest Windows NT Service Pack.

STATUS
Microsoft has confirmed this to be a problem in Windows NT version 4.0 SP2. This problem has been corrected in the latest U.S. Service Pack for Microsoft Windows NT version 4.0. For information on obtaining the Service Pack, query on the following word in the Microsoft Knowledge Base (without the spaces):

S E R V P A C K Additional query words: IP address NAK Keywords         : kbnetwork nttcp NTSrv Version          : 4.0 Platform         : winnt
 * }