Open Software Solutions

When you try to extract and to view the contents of a Microsoft Update Standalone Package (MSU) for Windows Vista, you cannot extract the files from the MSU.

For example, one of the following issues may occur:

•	If you try to use the /x command-line switch at a command prompt to extract the file on a Windows Vista-based computer, a dialog box that contains command-line help for the MSU opens.
•	If you try to open the file on a computer that is not running Windows Vista, you cannot open the file. Instead, Windows prompts you to locate the program that created the file.

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These issues may occur for the following reasons:

•	The /x command-line switch cannot be used to extract MSU packages.
•	MSU packages for Windows Vista use a file name extension that is not recognized by earlier versions of Windows.

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To resolve this issue, use the Windows Vista Expand command to extract and to view the files in an MSU. The Expand command is included in Windows Vista and in the Windows Vista OEM Pre-installation Kit (OPK).

Note The Windows Vista Expand command differs from the Expand command that is included in earlier versions of Windows.

To use the Windows Vista Expand command to expand the files from the MSU, follow these steps:

1.	If you are extracting a hotfix package, follow these steps: a. Double-click the Hotfix.exe file. b. In the Microsoft Self-Extractor dialog box, click Continue. c. In the Select the folder where you want to unzip the files to box, type C: MSUFolder, and then click OK. If you are not extracting a hotfix package, create a folder that is named C: MSUFolder, and then save the MSU file to this folder.
2.	At a command prompt, type the following commands. Press ENTER after each command. c: cd c: MSUFolder expand -F:* Saved_MSU_File_Name.msu c: MSUFolder expand -F:* Saved_MSU_File_Name.cab c: MSUFolder

The C: MSUFolder folder now contains one or more subfolders and files that have .mum and .manifest file name extensions. The subfolders contain the files that are updated by the MSU. The files describe the file operations, the registry modifications, and the other operations that need to be completed to install the component.

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The .cab file that is extracted from the MSU file uses Intra-Package Delta (IPD) compression technology. IPD technology reduces the download size of an MSU but still delivers a self-contained package that contains the updated files. A .cab file that uses IPD is known as an IPD-aware package. Other programs and tools may be unable to extract or to view the files in the IPD-aware package that is contained in an MSU file.

For example, the following programs and tools cannot extract or view the files in an IPD-aware package:

•	Windows Explorer
•	The Expand command that is included in earlier versions of Microsoft Windows.
•	The WinZip program from WinZip International LLC.

When you try to use one of these other programs or tools to extract the files from an IPD-aware package, only the binary deltas that are included in the .cab file may be extracted. The binary deltas file list may resemble the following:

The files that are named 0, 1, 2, and so on, are binary delta files. These files are used to synthesize the updated files when you install the update.

The following Windows Vista software updates are distributed in MSU packages that contain IPD technology:

•	Security updates
•	Critical updates
•	Updates
•	Update rollups
•	Hotfixes

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Information about the Windows Vista Expand command

Use the following syntax to run the Windows Vista Expand command:

Expand [-r] Source Destination
Expand -r Source [Destination]
Expand -D Source.cab [F:Files]
Expand Source.cab -F:Files Destination

The following table explains the Expand command syntax.

-r	Rename expanded files.
-D	Display the list of files in the source file.
Source	The path and the name of the source file. Wildcard characters may be used.
-F:Files	The names of files to expand from a .cab file.
Destination	The path and the name of the destination file or directory. If Source is multiple files and if you do not specify -r, Destination must be a directory.

The third-party products that this article discusses are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, about the performance or reliability of these products.

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