Windows 95/98 DHCP Client Modified for RFC2131 Retransmission Compliance (194790)


The information in this article applies to:

  • Microsoft Windows 98
  • Microsoft Windows 95
This article was previously published under Q194790

SYMPTOMS

Windows 95 or Windows 98-based computers using Dynamic Host Configuration Protocol (DHCP) may occasionally fail to lease an Internet Protocol (IP) address when the network or DHCP server is very busy.

CAUSE

This issue can occur because the DHCP client-retry mechanism in Windows 95 and Windows 98 is not in compliance with RFC 2131.

The current behavior is as follows:

  • Windows 95 running the standard Winsock 1.1 stack:

    - DHCP Request: 1 retry after 2 seconds
    - DHCP Discover: 3 retries, at 2-second intervals
  • Windows 98, and Windows 95 with the Winsock 2.0 update:

    - DHCP Request: 1 retry after 6 seconds
    - DHCP Discover: 3 retries, at 6-second intervals

RESOLUTION

A supported fix that corrects this problem for Windows 98 and for Windows 95 with the Windows Sockets 2.0 Update is now available from Microsoft, but has not been fully regression tested and should be applied only to computers experiencing this specific problem. To resolve this problem immediately, contact Microsoft Technical Support to obtain the fix. If you are not severely impacted by this specific problem, Microsoft recommends that you wait for the next service pack that contains this fix.

For a complete list of Microsoft Technical Support phone numbers and information on support costs, please go to the following address on the World Wide Web:

http://support.microsoft.com/default.aspx?scid=fh;EN-US;CNTACTMS



This fix, for Windows 98 only, should have the following file attributes (or later): 

   File name     Version    Date      Time     Size
   ---------------------------------------------------------
   Vdhcp.386     4.10.2012  06/22/98  01:12pm  56,175 bytes


This fix, for Windows 95 with the Windows Sockets 2.0 update only, should have the following file attributes (or later): 

   File name     Version    Date      Time     Size
   ---------------------------------------------------------
   Vdhcp.386     4.10.1658  10/20/98  10:25am  55,155 bytes
NOTE: This version of the Vdhcp.386 file is only compatible with Windows 95-based computers that have been updated to the Windows Sockets 2.0 version of the TCP/IP stack. For more information about this update, please see the following article in the Microsoft Knowledge Base:

ARTICLE-ID: 182108
TITLE : Availability of Windows Sockets 2.0 for Windows 95


STATUS

Microsoft has confirmed this to be a problem in Windows 98 and Windows 95.

This problem was corrected in Windows 98 Second Edition.

MORE INFORMATION

After you apply the fix listed earlier in this article, the DHCP client retry mechanism is modified to be comply with RFC 2131.

The current Windows NT DHCP client (Dhcpcsvc.dll) behaves as described in RFC 2131. It sends the first DHCP request plus up to 3 retries if needed.

For additional information about Windows 98 and Windows 98 Second Edition hotfixes, click the article number below to view the article in the Microsoft Knowledge Base:

206071 General Information About Windows 98 and Windows 98 Second Edition Hotfixes

For additional information about Windows 95 hotfixes, click the article number below to view the article in the Microsoft Knowledge Base:

161020 Implementing Windows 95 Updates

Modification Type:MinorLast Reviewed:9/22/2005
Keywords:kbHotfixServer kbQFE kbnetwork kbprb KB194790
©2004 Microsoft Corporation. All rights reserved.