Multiple CardBus Devices Cannot Share IRQs (279491)


The information in this article applies to:

  • Microsoft Windows 2000 Server SP1
  • Microsoft Windows 2000 Advanced Server SP1
  • Microsoft Windows 2000 Professional SP1
This article was previously published under Q279491
IMPORTANT: This article contains information about modifying the registry. Before you modify the registry, make sure to back it up and make sure that you understand how to restore the registry if a problem occurs. For information about how to back up, restore, and edit the registry, click the following article number to view the article in the Microsoft Knowledge Base:

256986 Description of the Microsoft Windows Registry

SYMPTOMS

A registry key was added in Windows 2000 Service Pack 1 (SP1) to change IRQ-routing settings for 16-bit CardBus controllers, and this registry key affects all CardBus controllers in a computer. Because some types of hardware may include multiple CardBus controllers, problems may occur if the multiple CardBus controllers try to share the same IRQ.

RESOLUTION

To resolve this problem, obtain the latest service pack for Windows 2000. For additional information, click the following article number to view the article in the Microsoft Knowledge Base:

260910 How to Obtain the Latest Windows 2000 Service Pack

The English version of this fix should have the following file attributes or later: 
   Date        Time    Version        Size     File name     Platform
   ------------------------------------------------------------------
   5/28/2001  09:24p      -           34,756     Ntdetect.com  Intel
   5/29/2001  09:28a  5.0.2195.3649   58,992     Pci.sys       Intel
   5/29/2001  09:28a  5.0.2195.3649  109,136     Pcmcia.sys    Intel

NOTE: To view the file version, right-click the file in Windows Explorer, click Properties, and then click the Version tab.

STATUS

Microsoft has confirmed that this is a problem in the Microsoft products that are listed at the beginning of this article. This problem was first corrected in Windows 2000 Service Pack 3.

MORE INFORMATION

For additional information about how to obtain a hotfix for Windows 2000 Datacenter Server, click the article number below to view the article in the Microsoft Knowledge Base:

265173 The Datacenter Program and Windows 2000 Datacenter Server Product

For additional information about how to install multiple hotfixes with only one reboot, click the article number below to view the article in the Microsoft Knowledge Base:

296861 Use QChain.exe to Install Multiple Hotfixes with One Reboot

This hotfix allows the use of multiple CardBus controllers in a single computer by sharing IRQs.

This hotfix allows the use of multiple CardBus controllers in a single computer by sharing IRQs. To use the hotfix with Windows 2000 SP3, you must change the registry to allow IRQ Routing. By default, IRQ routing is turned off in Windows 2000 SP3 to avoid any issues on computers that do not require this hotfix. To allow IRQ routing, follow these steps.

WARNING: If you use Registry Editor incorrectly, you may cause serious problems that may require you to reinstall your operating system. Microsoft cannot guarantee that you can solve problems that result from using Registry Editor incorrectly. Use Registry Editor at your own risk.
  1. Click Start, click Run, type regedit in the Open box, and then click OK.
  2. Locate the following registry subkey:

    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Pcmcia\Parameters

  3. On the Edit menu, point to New, and then click DWORD Value.
  4. In the New Value #1 box, type DisableIsaToPciRouting, and then press ENTER.
  5. Right-click DisableIsaToPciRouting, and then click Modify.
  6. In the Value data box, type 0 (zero), and then click OK.
  7. Quit Registry Editor.
Modification Type:MajorLast Reviewed:5/15/2006
Keywords:kbbug kbenv kbfix kbHardware kbOSWin2000fix kbQFE kbWin2000PreSP3Fix kbWin2000sp3fix kbHotfixServer KB279491
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