DOCUMENT:Q147872  25-MAR-2002  [win95x]
TITLE   :Unable to Lease IP Address from DHCP Server
PRODUCT :Microsoft Windows 95.x Retail Product
PROD/VER::
OPER/SYS:
KEYWORDS:kberrmsg kbnetwork kbpolicy win95kbfixlist

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The information in this article applies to:

 - Microsoft Windows 95 
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SYMPTOMS
========

When you are using Windows 95 with a DHCP server to assign an IP address, you
may receive the following error message if DHCP messages have not been disabled
in Windows 95:

   This DHCP client was unable to obtain an IP network address from a DHCP
   server.

If DHCP messages have been disabled, you may not see the error message even
though an IP address was not obtained.

This error can occur if the DHCP server does not respond to a DHCP request within
two seconds.

RESOLUTION
==========


STATUS
======

This problem no longer occurs in Windows 98. To resolve this problem, install
the current version of Windows. For information about the current version of
Windows, visit http://www.microsoft.com/windows.

MORE INFORMATION
================

When requesting an IP address from a DHCP server, Windows 95 times out the
requests at two-second intervals. After a timeout, the request is re- issued. If
the timeout has expired before the server responds, the response is discarded
and the client waits for a response to its latest request. This process
continues through four retries, at which time the error message stated above is
generated.

This problem does not occur with MSTCP-32 for Windows for Workgroups because it
uses a default timeout of four seconds.

This problem is known to occur when you are using DHCP servers that implement
address protection at the server. In particular, the problem occurs if it takes
the server more than two seconds to verify whether an address that it is
preparing to issue is already in use or not.

Address protection is the process of determining whether an address is in use by
another computer before a client uses it. Note that Microsoft DHCP clients
implement address protection at the client.


Additional query words: tcp/ip tcp protocol

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Keywords          : kberrmsg kbnetwork kbpolicy win95 kbfixlist
Technology        : kbWin95search kbZNotKeyword3
Version           : :
Issue type        : kbprb

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