Important This article contains information about how to modify the registry. Make sure that you back up the registry before you modify it. Make sure that you know how to restore the registry if a problem occurs. For more information about how to back up, restore, and modify the registry, click the following article number to view the article in the Microsoft Knowledge Base:
256986 Description of the Microsoft Windows registry
When a Microsoft Windows XP-based computer tries to enter standby, the computer stops responding (hangs).
This problem occurs when a driver tries to put a universal serial bus (USB) device into a Selective Suspend reduced-power state at the same time that Windows tries to enter standby. Specifically, this problem occurs because of a bug in the USB hub driver.
Warning Serious problems might occur if you modify the registry incorrectly by using Registry Editor or by using another method. These problems might require that you reinstall the operating system. Microsoft cannot guarantee that these problems can be solved. Modify the registry at your own risk.
To apply this hotfix, you must add a REG_BINARY value named FlushPortPowerIrpsFlag that has a value of 0x1 to the following registry subkey:
Click Start, click Run, type regedit in the Open box, and then click OK.
Locate and then click the following subkey in the registry:
On the Edit menu, point to New, and then click Binary Value.
Type FlushPortPowerIrpsFlag for the name of the Binary Value, and then press ENTER.
Right-click FlushPortPowerIrpsFlag, and then click Modify.
In the Value data box, type 01, and then click OK.
Exit Registry Editor.
A supported hotfix is available from Microsoft. However, this hotfix is intended to correct only the problem that is described in this article. Apply this hotfix only to systems that are experiencing this specific problem. This hotfix might receive additional testing. Therefore, if you are not severely affected by this problem, we recommend that you wait for the next software update that contains this hotfix.
If the hotfix is available for download, there is a "Hotfix download available" section at the top of this Knowledge Base article. If this section does not appear, contact Microsoft Customer Service and Support to obtain the hotfix.
Note If additional issues occur or if any troubleshooting is required, you might have to create a separate service request. The usual support costs will apply to additional support questions and issues that do not qualify for this specific hotfix. For a complete list of Microsoft Customer Service and Support telephone numbers or to create a separate service request, visit the following Microsoft Web site:
Note The "Hotfix download available" form displays the languages for which the hotfix is available. If you do not see your language, it is because a hotfix is not available for that language.
The English version of this hotfix 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 tool in Control Panel.
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.
In Windows XP, USB devices may support the Selective Suspend feature. A driver that supports the Selective Suspend feature can disable the USB device that the driver controls when the device becomes idle. This is true even when the computer remains in a fully operational power state (S0).
For example, a driver can idle the host controller. A driver can also idle empty USB hubs and certain USB devices that the operating system supports. The Selective Suspend feature conserves battery power in portable computers and in Tablet PC computers. Typically, USB controllers use significant battery power, even when no devices are attached to the computer.For more information, click the following article number to view the article in the Microsoft Knowledge Base:
824684Description of the standard terminology that is used to describe Microsoft software updates