Open Software Solutions

You experience the following symptoms on a computer that is running Windows Vista:

•	The Allow hybrid sleep option is missing from the Advanced settings tab of the Power Options dialog box in Windows Vista.
•	When you run the powercfg.exe -a command to list the power states that are supported on the computer, the output that appears includes the following lines: The system firmware does not support this standby state. Hybrid Sleep

These symptoms occur intermittently. When you restart the computer, the Allow hybrid sleep option reappears. Additionally, when you run the powercfg.exe -a command again, the output that appears includes a line that resembles the following:

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This problem occurs in scenarios where a race condition exists between the Monitor.sys driver and a kernel setting.

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Hotfix information

A supported hotfix is now 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 service pack that contains this hotfix.

To resolve this problem, submit a request to Microsoft Online Customer Services to obtain the hotfix. To submit an online request to obtain the hotfix, visit the following Microsoft Web site:

Note If additional issues occur or 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. To create a separate service request, visit the following Microsoft Web site:

File information

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 item in Control Panel.

Windows Vista, x86-based versions

File name	File version	File size	Date	Time	Platform
Update.mum	Not Applicable	1,996	17-Apr-2007	17:25	Not Applicable
X86_38842e8a9920e87789f15cf51c83f457_31bf3856ad364e35_6.0.6000.20580_none_2f7466c1b5f35f7a.manifest	Not Applicable	697	17-Apr-2007	17:25	Not Applicable
X86_microsoft-windows-os-kernel_31bf3856ad364e35_6.0.6000.20580_none_6a7d3c99d05b067b.manifest	Not Applicable	18,778	17-Apr-2007	17:27	Not Applicable
Ntkrnlpa.exe	6.0.6000.20580	3,504,312	17-Apr-2007	02:37	Not Applicable
Ntoskrnl.exe	6.0.6000.20580	3,469,496	17-Apr-2007	02:37	Not Applicable

Windows Vista, 64-bit versions

File name	File version	File size	Date	Time	Platform
Amd64_c3962e8cefe18a3d9bff5b6e3518e8b0_31bf3856ad364e35_6.0.6000.20580_none_f3bf013ca2ba0f1d.manifest	Not Applicable	701	17-Apr-2007	17:25	Not Applicable
Amd64_microsoft-windows-os-kernel_31bf3856ad364e35_6.0.6000.20580_none_c69bd81d88b877b1.manifest	Not Applicable	17,330	17-Apr-2007	17:31	Not Applicable
Update.mum	Not Applicable	2,008	17-Apr-2007	17:25	Not Applicable
Ntoskrnl.exe	6.0.6000.20580	4,431,032	17-Apr-2007	03:54	x64

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

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For more information about the Powercfg.exe tool in Windows Vista, visit the following Microsoft Web site:

For more information about terminology that is used to describe Microsoft software updates, click the following article number to view the article in the Microsoft Knowledge Base:

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