"0xC000009A" error message when you try to install Windows 7 SP1 or Windows Server 2008 R2 SP1

When you try to install Windows 7 Service Pack 1 (SP1) or Windows Server 2008 R2 Service Pack 1 (SP1) on a computer that has more than 10 language packs installed, the computer stops responding at a black screen. Additionally, you receive an "0xC000009A" error message.

This issue occurs because the number of open registry key handles for subkeys that have the same name is limited to 65,535 in the registry. Each language pack that is installed on the computer increases the number of open registry key handles.

You must install this update to resolve this issue before you install Windows 7 SP1 or Windows Server 2008 R2 SP1.

Update information

How to obtain this update

The following files are available for download from the Microsoft Download Center:
For more information about how to download Microsoft support files, click the following article number to view the article in the Microsoft Knowledge Base: Microsoft scanned this file for viruses. Microsoft used the most current virus-detection software that was available on the date that the file was posted. The file is stored on security-enhanced servers that help prevent any unauthorized changes to the file.

Prerequisites

To apply this update, you must be running one of the following operating systems:

• Windows 7
• Windows 7 Service Pack 1 (SP1)
• Windows Server 2008 R2
• Windows Server 2008 R2 Service Pack 1 (SP1)

For more information about how to obtain a Windows 7 or a Windows Server 2008 R2 service pack, click the following article number to view the article in the Microsoft Knowledge Base:

Registry information

To use the update 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 update.

Update replacement information

This update does not replace a previously released update.

File information

The global version of this update 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

• The files that apply to a specific product, milestone (RTM, SPn), and service branch (LDR, GDR) can be identified by examining the file version numbers as shown in the following table:
  Collapse this tableExpand this table

  Version	Product	Milestone	Service branch
  6.1.760 0.16xxx	Windows 7 and Windows Server 2008 R2	RTM	GDR
  6.1.760 0.20xxx	Windows 7 and Windows Server 2008 R2	RTM	LDR
  6.1.760 1.17xxx	Windows 7 and Windows Server 2008 R2	SP1	GDR
  6.1.760 1.21xxx	Windows 7 and Windows Server 2008 R2	SP1	LDR

• GDR service branches contain only those fixes that are widely released to address widespread, extremely important issues. LDR service branches contain hotfixes in addition to widely released fixes.
• 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 maintain the state of the updated components. 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

For more information about software update terminology, click the following article number to view the article in the Microsoft Knowledge Base: For more information about how to recover from this issue or how to work around this issue, visit the following Microsoft website:You can also use the lpksetup.exe /u language command to uninstall language packs.

Notelanguage is a placeholder for the code of the language pack that you want to uninstall.

For example, assume that you want to uninstall the Japanese and the Spanish language packs. To do this, open a command prompt, type the following command, and then press Enter:For more information about Lpksetup command-line options, visit the following Microsoft TechNet website:

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