DOCUMENT:Q136951  08-AUG-2001  [winnt]
TITLE   :Released Client IP Address Shows As Active in DHCP Server
PRODUCT :Microsoft Windows NT
PROD/VER:3.51
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Windows NT Server version 3.51 
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SYMPTOMS
========

If you run IPCONFIG/RELEASE (or WINIPCFG/RELEASE from Windows95) from a
DHCP-enabled client computer and the client computer is located on a different
subnet than the DHCP server, the IP address is released but the address shows up
in the active lease database on the DHCP server.

CAUSE
=====

This problem occurs because the DHCP server is not checking the DHCP release
packet correctly. Because the release packet is sent directly to the server, the
BOOTP relay agent does not add header information, but the client's IP address
is in the CIADDR field of the packet. The DHCP server is not looking at the
CIADDR field and assumes the packet is for a local scope. The DHCP server fails
to find the client's UID and the release fails.


RESOLUTION
==========

To work around this problem, manually delete the active lease using DHCP
Manager.

STATUS
======

Microsoft has confirmed this to be a problem in Windows NT version 3.51. This
problem has been corrected in the latest U.S. Service Pack for Windows NT
version 3.51. 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: prodnt tcpip dhcp unavailable

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Keywords          :  
Technology        : kbWinNTsearch kbWinNT351search kbWinNTSsearch kbWinNTS351 kbWinNTS351search
Version           : 3.51

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