DOCUMENT:Q125514  08-AUG-2001  [crossnet]
TITLE   :TCP/IP-32 Client Cannot Obtain DHCP Lease
PRODUCT :Windows for Workgroups and Windows NT Networking Issues
PROD/VER:WINDOWS:3.11; winnt:3.5; :3.11a
OPER/SYS:
KEYWORDS:

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The information in this article applies to:

 - Microsoft Windows NT Server version 3.5 
 - Microsoft TCP/IP-32 for Windows for Workgroups, version 3.11a 
 - Microsoft Windows for Workgroups version 3.11 
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SUMMARY
=======

A Microsoft Windows for Workgroups client using Microsoft TCP/IP-32 Dynamic Host
Configuration Protocol (DHCP) on the same network segment as a Microsoft Windows
NT 3.5 DHCP Server may not be able to obtain an IP address lease if the DHCP
server is incorrectly configured.

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

If the DHCP server is assigned a Class B IP address, it must also have its DHCP
scope configured for Class B addresses or it will not respond with an offer
message when it receives a discover message from a DHCP client.

Example
-------

A DHCP server is assigned a Class B IP address. However, it is configured to
lease DHCP clients Class C IP addresses, that is, its DHCP scope is configured
as Class C. Because the DHCP client is on the same segment, its discover message
is not routed and thus the giaddr field is not modified by an RFC 1542 compliant
router. Noticing that the giaddr field has not been modified, the server assumes
the client is on the same subnet and uses its own IP information (IP address and
subnet mask) for its DHCP offer message.

Additional query words: prodtcp32 prodtcp 3.11 wfw wfwg TCP/IP fail

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Keywords          :  
Technology        : kbWinNTsearch kbWinNT350search kbWinNTSsearch kbWinNTS350 kbWinNTS350search kbAudDeveloper kbTCPIPSearch kbWFWSearch kbZNotKeyword3 kbWFW311 kbTCPIP311a
Version           : WINDOWS:3.11; winnt:3.5; :3.11a

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