You cannot access a volume in Windows 7 or in Windows 2008 R2 when the volume is encrypted by a third-party encryption driver

Consider the following scenario:

• You have a computer that is running Windows 7 or Windows Server 2008 R2.
• You encrypt a nonsystem volume by using a third-party encryption driver.
• A third-party encryption key is configured in this application.

In this scenario, you cannot access the encrypted volume even though you have the third-party encryption key.

This issue occurs because the BitLocker driver incorrectly recognizes the state of its internal volume context as a "failed initialization" state. This behavior occurs when the BitLocker driver cannot access the volume and then receives a STATUS_ACCESS_DENIED error. Therefore, the incorrect state causes all I/O requests that are sent to the volume to be blocked.

Note This hotfix causes the BitLocker driver to retry the volume context initialization after the STATUS_ACCESS_DENIED error occurs. This behavior lets you access the volume.

Hotfix information

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 the problem described in this article. 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.

Prerequisites

To apply this hotfix, you must be running Windows 7 or Windows Server 2008 R2 on the computer.

Registry information

To use this hotfix, you do not have to change the registry.

Restart requirement

You must restart the computer after you apply this hotfix.

Hotfix replacement information

This hotfix does not replace a previously released hotfix.

File information

The global version of this hotfix installs files that have the attributes that are listed in the following tables. The dates and the times for these files are listed in Coordinated Universal Time (UTC). The dates and the times for these files on your local computer are displayed in your local time together with your current daylight saving time (DST) bias. Additionally, the dates and the times may change when you perform certain operations on the files.

Windows 7 and Windows Server 2008 R2 file information notes

Important Windows 7 hotfixes and Windows Server 2008 R2 hotfixes are included in the same packages. However, hotfixes on the Hotfix Request page are listed under both operating systems. To request the hotfix package that applies to one or both operating systems, select the hotfix that is listed under "Windows 7/Windows Server 2008 R2" on the page. Always refer to the "Applies To" section in articles to determine the actual operating system that each hotfix applies to.

• The MANIFEST files (.manifest) and the MUM files (.mum) that are installed for each environment are listed separately in the "Additional file information for Windows Server 2008 R2 and for Windows 7" section. MUM and MANIFEST files, and the associated security catalog (.cat) files, are extremely important to maintaining the state of the updated component. The security catalog files, for which the attributes are not listed, are signed with a Microsoft digital signature.

For all supported x86-based versions of Windows 7

For all supported x64-based versions of Windows 7 and of Windows Server 2008 R2

For all supported IA-64-based versions of Windows Server 2008 R2

To work around this issue, disable the BitLocker Drive Encryption feature. To do this, follow these steps:

1. Click Start, click Control Panel, and then click BitLocker Drive Encryption.
2. On the BitLocker Drive Encryption page, find the volume on which you want to turn off the BitLocker Drive Encryption feature. Then, click Turn Off BitLocker.
3. In the What level of decryption do you want dialog box, click either Disable BitLocker Drive Encryption or Decrypt the volume as needed.

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

For more information about the BitLocker Drive Encryption feature, visit the following Microsoft TechNet Web sites: For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base:

Additional file information

Additional file information for Windows 7 and for Windows Server 2008 R2

Additional files for all supported x86-based versions of Windows 7

Additional files for all supported x64-based versions of Windows 7 and of Windows Server 2008 R2

Additional files for all supported IA-64-based versions of Windows Server 2008 R2