A Windows Portable Devices (WPD) application crashes intermittently on a computer that is running Windows 7

Applies to: Windows 7 EnterpriseWindows 7 Home BasicWindows 7 Home Premium


Applications that are built on Windows Portable Devices (WPD) may crash intermittently on a computer that is running Windows 7. This issue occurs in the following scenarios:
  • When the system resumes from sleep.
  • When you transfer content from the computer to a portable device.
  • When you read properties from a portable device, or write properties to a portable device.
For example, you may see this issue in Zune software when you sync media files to a Zune device from a computer that is running Windows 7.

This issue affects applications such as the Zune client application (Zune software), Windows Media Player and some third-party applications.


This is a timing issue. It occurs because of an error during the scheduling of the ThreadPool tasks. The error results in heap corruption in the application.


Hotfix information

A supported hotfix is now available from Microsoft. However, it is intended to correct only the problem that is described in this article. Apply it only to systems that are experiencing this specific problem. This hotfix may 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.

To resolve this problem immediately, contact Microsoft Customer Support Services to obtain the hotfix. For a complete list of Microsoft Customer Support Services telephone numbers and information about support costs, visit the following Microsoft Web site:Note In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The usual support costs will apply to additional support questions and issues that do not qualify for the specific update in question.


To apply this hotfix, you must have Windows 7 installed.

Restart requirement

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

Hotfix replacement information

This hotfix does not replace a previously released hotfix.

Registry information

To use one of the hotfixes in this package, you do not have to make any changes to the registry.

File information

The English version of this 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.

For all supported x86-based versions of Windows 7

File nameFile versionFile sizeDateTimePlatform
Portabledeviceapi.mofNot Applicable5,10510-Jun-200921:46Not Applicable
Portabledeviceclassextension.mofNot Applicable3,20210-Jun-200921:46Not Applicable
Portabledeviceconnectapi.mofNot Applicable1,77710-Jun-200921:46Not Applicable
Portabledevicetypes.mofNot Applicable3,49010-Jun-200921:46Not Applicable

For all supported x64-based versions of Windows 7

File nameFile versionFile sizeDateTimePlatform
Portabledeviceapi.mofNot Applicable5,10510-Jun-200921:07Not Applicable
Portabledeviceclassextension.mofNot Applicable3,20210-Jun-200921:07Not Applicable
Portabledeviceconnectapi.mofNot Applicable1,77710-Jun-200921:07Not Applicable
Portabledevicetypes.mofNot Applicable3,49010-Jun-200921:07Not Applicable


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

More Information

For more information about Windows Portable Devices, visit the following Microsoft Web site:
For more information about the ThreadPool class, visit the following Microsoft Web site:


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