Error message when you try to open a 3DES encrypted file that is migrated from Windows XP to Windows 7 or to Windows Server 2008 R2: "Access Denied"

Consider the following scenario:

• On a computer that is running Windows XP, you use the 3DES algorithm to encrypt a file.
  
  Note For more information about how to use 3DES algorithm to encrypt files, see the "More information" section.
• You migrate the encrypted file to another computer that is running Windows 7 or Windows Server 2008 R2. For example, you use Ntbackup.exe to back up an encrypted file. Then, you restore the file on a computer that is running Windows 7 or Windows Server 2008 R2.
  
  Note Ntbackup.exe preserves the encryption attributes of the Encrypting File System (EFS).

In this scenario, you cannot open the migrated encrypted file. Additionally, you receive the following error message: Note This issue does not occur when you use the DESX algorithm or the AES256 algorithm to encrypt files on computers that are running Windows XP.

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

There are no prerequisites.

Registry information

To use the hotfix in this package, you do not have to make any changes to 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 English (United States) version of this hotfix installs files that have the attributes that are listed in the following tables. The dates and times for these files are listed in Coordinated Universal Time (UTC). The dates and times for these files on your local computer are displayed in your local time and with your current daylight saving time (DST) bias. Additionally, the dates and times may change when you perform certain operations on the files.

Windows 7 and Windows Server 2008 R2 file information notes

Important Windows 7 and Windows Server 2008 R2 hotfixes are included in the same packages. However, only one of these products may be listed on the "Hotfix Request" page. To request the hotfix package that applies to both Windows 7 and Windows Server 2008 R2, just select the product that is listed on the page.

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

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

For more information about how to use the 3DES algorithm to encrypt files on a computer that is running Windows XP, visit the following Microsoft Knowledge Base article:For more information about Ntbackup.exe, visit the following Microsoft Web site: For more information about encryption algorithms, visit the following Microsoft Web site:For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base: