What is Microsoft Windows System Image Manager (SIM)?

What is Microsoft Windows System Image Manager used for?

A tool in the Windows Assessment and Deployment Kit (ADK), Windows SIM provides a graphical user interface (GUI) to help system admins create unattended Windows Setup answer files for installing the Windows OS.

An answer file is an extensible markup language (XML)-based file that houses Windows Setup information, including how to partition disks and which product key to use. These files, and the information contained within them, are needed to configure and customize the default Windows installation.

IT teams can create answer files with Windows SIM using information from a Windows image file and a catalog file. They can then use the files to automate Windows Setup and modify the settings of a Windows image, such as the default language.

Windows SIM also displays all the configurable component settings within a Windows image. It allows IT professionals to add third-party applications, device drivers, language packs and more to the answer files.

"Unattended" setup in answer files means the OS setup and configuration are automated in the file. After adding the required component settings to an unattended answer file, IT can view the available settings for each component. They can also customize the settings to satisfy a user's or the organization's needs. For example, IT can customize the language settings, the partitions to create during installation and more.

Here are some of the most common scenarios for using Windows SIM:

• Create catalog files and new answer files for a Windows image;
• Add components, packages or other updates to existing answer files;
• Validate answer file component settings against the settings in a Windows image;
• Add device drivers (in-box and out-of-box) during Windows Setup;
• Add applications or drivers to be installed during Windows Setup using a distribution share;
• Add applications, scripts and other binary files by using a data image;
• Make offline updates (including software updates, device drivers and language packs) to a Windows image;
• Create small, portable configuration sets to be called explicitly in an answer file for installations that cannot access a larger distribution share;
• Import packages that are not part of a Windows image file to a distribution share.

How Windows SIM works

Two types of files are needed for Windows SIM to create answer files (Unattend.xml). These are the Windows image (.wim) files and catalog (.clg) files. Windows SIM uses these files to display the available components and packages. These elements can be added to an answer file. The components section contains the component settings to be applied during Windows Setup.

The configuration settings are organized into configuration passes. One example of a configuration pass is offline servicing, which is when the installation process applies the packages (software updates, drivers and language packs) in an answer file to the Windows image. Teams can add the components by right-clicking on the one they want in the catalog file and moving it to the answer file. The packages section contains Windows features and the information needed to distribute software updates, service packs and language packs.

Once the answer file is created, it configures and customizes the default Windows installation during Windows Setup. The .wim and .clg files also contain configurable settings that IT personnel can modify after a component or package has been added to an answer file.

How to use Windows System Image Manager

To use Windows SIM to create unattended answer files, first IT personnel must have the required permissions to access the install.wim file for the OS being installed. This access is needed to create, validate, and manage the answer file and provide the correct options for customizing the default Windows installation.

During Windows Setup, the Windows SIM answer file applies the chosen settings to the Windows installation. Windows SIM does not modify the Windows image or the settings in a Windows image file.

The first step in using an answer file with Windows SIM is to create a catalog file. When creating this file, Windows SIM queries the Windows image for a list of all the settings and states in that image.

The catalog file is a binary file containing a writable version of the install.wim file located in the Windows installation media Sources folder; the administrator uses the installation media to install the OS. The catalog file contains and displays all the configurable settings in a Windows image and information about the settings' status. Microsoft recommends using the 32-bit version of Windows SIM to create catalog files.

Once the catalog file is set, IT teams create an answer file by clicking on File in Windows SIM, and then clicking on New Answer File. Once the answer file is in place, they can add components, properties and other resources to it, or customize different aspects of Windows using the answer file and Windows SIM. They can also add properties to the answer file that automate parts of the installation process such as automatically accepting the Windows End-User License Agreement.

IT can include other resources such as third-party drivers, scripts or applications from a distribution share, which is an optional storage folder. IT can also pick smaller, more portable sections of a distribution share, known as a configuration set, which contains files the answer file explicitly calls for. These files are saved in a specific folder that IT chooses. The paths to the files automatically update to that folder.

In addition, IT can import any packages -- which contain instructions for adding or removing applications -- that are not part of the Windows image to the distribution share. IT can then take the packages from the distribution share and apply them to the answer file.

To add even more resources, such as binary files, administrators can use a data image. First, open the Windows Deployment Image Servicing and Management command-line tool to create a folder with the resources. During this process, specify where the data image goes in the Windows image with the DataImage setting. It's also possible to indicate where to send binary files using the $OEM$ folder. Finally, pick which disk -- or disks -- to install the OS on. Windows SIM allows IT to change the Windows image while offline, including altering software, device drivers, language packs and more.

Windows SIM user interface and panes

The Windows SIM GUI is divided into five sections, which Microsoft calls "panes." IT teams can use these multi-purpose panes to create unattended answer files, and then add components and packages to the respective configuration passes in an answer file. IT personnel can also use the panes to open Windows image files.

Each of the five panes in Windows SIM has a specific name. One is the Distribution Share pane. IT teams can use this pane to view the currently open distribution share folder in the tree. They can also create and explore new distribution folders by right-clicking in the pane, or add items from a distribution file to an answer file by right-clicking that item.

The second pane in Windows SIM is the Answer File pane. This section displays information on Windows Setup configuration passes, including the settings to apply in each pass and which packages Windows Setup will install. IT personnel can also create, open and change answer files from this pane.

The Windows Image pane shows a tree view of the currently open Windows image. IT teams can view everything within the image, including its components and packages from this pane. They can then use this information to determine which components and packages need to be added to an answer file in the Answer File pane.

The Properties pane displays all the settings and properties for a particular package or component. IT can use this pane to change component settings and package Windows feature selections.

Finally, the Messages pane shows information about issues and where they are happening. It contains three tabs -- XML, Validation and Configuration Set. Clicking on any of these tabs allows IT staff to see the issue location, as well as the type and description of the issue message. While all three tabs can contain messages, IT can only see messages in the Configuration Set tab if a configuration set has already been created.

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