FIX: Error message when a Windows CE 5.0-based device has more than one network adapter: "DHCP was unable to obtain an IP address"

View products that this article applies to.

SYMPTOMS

When a Microsoft Windows CE 5.0-based device has more than one network adapter, you may receive the following error message:

DHCP was unable to obtain an IP address. If the netcard is removable, then you can remove/reinsert it to have DHCP make another attempt to obtain an IP address for it. Otherwise, you can statically assign an address.

Additionally, IP address 0.0.0.0 is assigned to a network adapter. However, you expect the Automatic IP process to generate IP address 169.254.x.x.

This problem occurs if the following conditions are true:

A network adapter that is named adapter A is connected to a hub that has a Dynamic Host Configuration Protocol (DHCP) server.
A network adapter that is named adapter B is connected to a hub that does not have a DHCP server.
Adapter A obtains an IP address when any DHCP packets are sent from adapter B.

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CAUSE

This problem occurs because a flag is set to true incorrectly when the server receives a DHCP packet from another network adapter. The flag is used to mark whether a DHCP server connects to a network adapter.

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RESOLUTION

Software update information

A supported software update is now available from Microsoft as Windows CE 5.0 Platform Builder Monthly Update (July 2008). You can confirm this by scrolling to the "File information" section of this article. The package file name contains the product version, date, Knowledge Base article number, and processor type. The package file name format is:

Product version-yymmdd-kbnnnnnn-processor type

For example: Wincepb50-060503-kb917590-armv4i.msi is the ARMV4i Windows CE 5.0 Platform Builder fix that is documented in KB article 917590 and that is contained in the May 2006 monthly update. To resolve this problem immediately, click the following article number for information about obtaining Windows CE Platform Builder and core operating system software updates:

837392 (http://support.microsoft.com/kb/837392/ ) How to locate core operating system fixes for Microsoft Windows CE Platform Builder products

Prerequisites

This update is supported only if all previously issued updates for this product are also installed.

Restart requirement

After you apply this update, you must perform a clean build of the whole platform. To do this, use one of the following methods:

On the Build OS menu, make sure that the following options are selected, and then click Sysgen.
- Clean Before Building
- Copy Files to Release Directory After Build
- Make Run-Time Image After Build
On the Build OS menu, click Open Release Directory, type blddemo clean -q at the command prompt, and then press ENTER.

You do not have to restart the computer after you apply this update.

Update replacement information

This update does not replace any other updates.

File information

The English version of this package has the file attributes (or later file attributes) that are listed in the following table.

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File name	File size	Date	Time
Wincepb50-080724-kb954904-armv4i.msi	622,080	25-Jul-2008	17:50
Wincepb50-080724-kb954904-mipsii.msi	631,296	25-Jul-2008	17:50
Wincepb50-080724-kb954904-mipsii_fp.msi	631,296	25-Jul-2008	17:50
Wincepb50-080724-kb954904-mipsiv.msi	633,856	25-Jul-2008	17:50
Wincepb50-080724-kb954904-mipsiv_fp.msi	633,856	25-Jul-2008	17:50
Wincepb50-080724-kb954904-sh4.msi	619,520	25-Jul-2008	17:50
Wincepb50-080724-kb954904-x86.msi	605,696	25-Jul-2008	17:50

The English version of this update has the file attributes (or later file attributes) that are listed in the following table. The dates and times for these files are listed in Coordinated Universal Time (UTC). When you view the file information, it is converted to local time. To find the difference between UTC and local time, use the Time Zone tab in the Date and Time item in Control Panel.

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File name	File size	Date	Time	Path
Packet.c	32,642	22-Jul-2008	20:51	Private\Winceos\Comm\Dhcp
Dhcp.lib	312,268	22-Jul-2008	20:50	Public\Common\Oak\Lib\Armv4i\Debug
Dhcp.lib	166,352	22-Jul-2008	20:50	Public\Common\Oak\Lib\Armv4i\Retail
Dhcp.lib	317,266	22-Jul-2008	20:50	Public\Common\Oak\Lib\Mipsii\Debug
Dhcp.lib	171,322	22-Jul-2008	20:50	Public\Common\Oak\Lib\Mipsii\Retail
Dhcp.lib	317,304	22-Jul-2008	20:51	Public\Common\Oak\Lib\Mipsii_fp\Debug
Dhcp.lib	171,342	22-Jul-2008	20:51	Public\Common\Oak\Lib\Mipsii_fp\Retail
Dhcp.lib	321,628	22-Jul-2008	20:51	Public\Common\Oak\Lib\Mipsiv\Debug
Dhcp.lib	172,436	22-Jul-2008	20:51	Public\Common\Oak\Lib\Mipsiv\Retail
Dhcp.lib	321,670	22-Jul-2008	20:51	Public\Common\Oak\Lib\Mipsiv_fp\Debug
Dhcp.lib	172,458	22-Jul-2008	20:51	Public\Common\Oak\Lib\Mipsiv_fp\Retail
Dhcp.lib	281,334	22-Jul-2008	20:50	Public\Common\Oak\Lib\Sh4\Debug
Dhcp.lib	154,972	22-Jul-2008	20:50	Public\Common\Oak\Lib\Sh4\Retail
Dhcp.lib	276,554	22-Jul-2008	20:50	Public\Common\Oak\Lib\X86\Debug
Dhcp.lib	149,658	22-Jul-2008	20:50	Public\Common\Oak\Lib\X86\Retail

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STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.

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MORE INFORMATION

For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:

824684 (http://support.microsoft.com/kb/824684/ ) Description of the standard terminology that is used to describe Microsoft software updates

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Steps to reproduce the problem

Assume that you have adapter A and adapter B that are described in the "Symptoms" section on a Windows CE 5.0-based device.
Disable adapter A, and then enable adapter B to obtain the DHCP address.
Enable adapter A to obtain the IP address.
On an available DHCP client from the network of adapter B, run the following commands several times:
ipconfig/release

ipconfig/renew

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