By Kushal Koolwal, R&D OS Engineer, VersaLogic Corp.
A technical white paper comparing the differences between WES7 and WES2009 in regards to building and deploying a fully-functional Windows Embedded image on a target device.
This paper describes some of the differences between Windows Embedded Standard 7 (WES7) and Windows Embedded Standard 2009 (WES2009). WES7 is the next generation offering in Microsoft's family of embedded operating systems. Specifically, WES7 is the successor to WES2009, which in turn was the successor to Windows XP Embedded (XPe). The goal is to provide OEM developers with a detailed understanding of the differences between the two embedded products in regards to building and deploying a fully-functional Windows Embedded image on a target device. Specifically, this paper will highlight the major differences of the development tools, features, driver packages and the overall practical experience in building and deploying images.
As a point of reference for this paper we used a VersaLogic Mamba (VL-EBX-37) single board computer (SBC) with an Intel Core 2 Duo processor (Intel Montevina platform) as the target device. A WES 2009 image was first built using the familiar Windows Embedded Studio tools (Target Designer, Component Designer and Component Database Manager) and then deployed on the target hardware. Similarly, an image was created and deployed using WES7 and its new development tools (ICE, IBW, ImageX, etc.). In the process, all differences between WES2009 and WES7 that were encountered through the experience of building and installing the embedded images were noted.
In this section we present the differences between the two products based on various categories.
The following table shows the differences in minimum requirements between WES2009 and WES7 for both the development and target systems:
|Development (Host) System|
|Host OS||Windows XP/Vista||Windows 7/Vista|
|CPU Speed||1 GHz||1 GHz|
|RAM||512 MB||1 GB|
|.NET Framework||3.0||3.5 (SP1)|
|SQL Server Express||2005 or later||N/A|
|Storage Space||5 GB||7 GB|
|Processor Architecture||32-bit only||32-bit and 64-bit (SMP1)|
|CPU Speed (min.)||728 MHz||1 GHz|
|RAM (min.)||256 MB||512 MB|
|Storage (min.)||126 MB||1 GB|
Migrating to WES7 represents a significant change in hardware and software requirements for both the development and target systems. At the same time, WES7 can take advantage of the higher performance from the 64-bit counterpart systems.
Starting from WES7, installing Windows Embedded is only supported2 on an NTFS file system. WES2009, on the other hand, supports installation on both FAT32 and NTFS  file systems. However, WES7 does support reading and writing to a FAT32 partition.
If your existing production system is a multi-boot OS environment in which one or more OSs are installed on a FAT32 partition and they share data with a WES2009 partition, you would have to make necessary adjustments to your storage partition structure before you migrate to WES7 because FAT32 cannot access NTFS partitions.
One of the great and much awaited features in WES7 is Hardware Abstraction Layer (HAL) independence, which means that one can maintain a single Windows image that can boot on various computer platforms without having to reinstall or maintain separate images for each platform. For example, in WES2009 an OEM developer had to select one and only one particular HAL type from the following :
For example, if there are two similar target systems, say a 586-based system (which requires the Advanced Configuration and Power Interface (ACPI) PC HAL) and a 686-based system (which requires the ACPI Uni/Multi-processor PC HAL), you will need to create and maintain two separate images (one for each system), even though most of the hardware (IDE, Ethernet, video, audio, etc.) is the same on both systems. With WES7, there is no such thing as HALs; it just has a single HAL which automatically takes care of different x86-based platform architectures and hence the same core image will now boot on both platforms. However, you must maintain separate images for 32-bit and 64-bit systems. WIM (Windows Imaging Format) technologies and an ImageX tool enable developers to take advantage of HAL independence. Please see the section "Maintaining Images" for more details.
Having HAL independence enables OEM developers to save time and effort by having a single core image that can boot across all platforms; there is no longer a need to maintain multiple platform-specific images.
You can install WES2009 on target boards that do not have ACPI, since Windows XP supports non-ACPI HAL types which WES7 does not support. WES73 requires ACPI to be present on the target computer; otherwise WES7 installation fails with a "BIOS (firmware) is not ACPI compliant" error message. Also, you need ACPI 2.0 or greater  and APCI support, at least at the BIOS (firmware) level4, in order for WES7 to install on your target board; otherwise you will likely see errors during installation.
|Installs with ACPI||Yes||Yes|
|Installs without ACPI||Yes||No|
|ACPI Version||Any||2.0 or greater|
In embedded applications there are many low-cost, low-power boards that are designed for a highly specialized purpose, often without any support for ACPI, which in turn makes them incompatible with WES7. In such a scenario, you will have to continue to use WES2009.
The toolkit in WES7 has a completely different set of tools than WES2009 for configuring and building images.
|Target Designer + Component Designer||Image Configuration Editor (ICE)|
|Component Database + Repositories||Distribution Share|
|SLX (Project File)||XML (Project File, aka Answer File)|
|9000 Drivers (as Components)||500 Drivers|
|1000 OS Components||150 OS Feature Set|
As shown in the table above, WES7 comes with an entirely different set of tools than WES2009. Tools like Target Designer, Component Database Manager and Component Designer are no longer present in WES7. Instead, WES7 comes with a master IDE tool called Image Configuration Editor (ICE) which encompasses most of the functionality of the WES2009 tools. Tasks like adding 3rd party drivers, custom files, applications, etc., which were accomplished using the Component Designer in WES2009, are now achieved in WES7 using the "$OEM$"5 and "Out-of-box Drivers" folders (contained within each Distribution Share). Also, tasks like adding registry entries, executing a program (batch/.exe file), etc. are accomplished by setting the SMI properties of the WES7 core components in ICE. Please see Appendix II: Example - Adding 3rd Party Materials for a step-by-step example.
WES7 includes two Distribution Shares (DSs): one each for 32-bit and 64-bit architectures. These DSs provide respective applications and drivers for each of the architecture types.
As WES7 is completely based on Vista/Windows 7 technologies, there is considerable change in their runtime image sizes due to the fundamental change in the building blocks of the OS (i.e., components). Components in WES2009 are replaced by Feature Sets and Driver Packages, which are an aggregation of the WES2009 components. With WES2009, one could create a bootable image at just under 50 MB. With WES7, a minimum bootable image is around 300 MB (almost 6 times larger in size). A relatively large image size in WES7 can also be attributed to the way in which Vista/Windows 7 is designed as it requires more space to install compared to Windows XP.
In WES2009, all of the OS building blocks (like drivers and components) were provided as Components which provided no clear distinction between drivers and OS components. For example, OS components like Windows Media Player, Remote Desktop, Internet Explorer and a driver for an AMD PCNET Ethernet adapter were all categorized as Components.
Moreover, with 10,000+ components in WES2009, it is very challenging for OEM developers to build a bootable image the first time without missing boot-critical components. WES7 simplifies this by providing an eCore (Embedded Core) package which gets included in every project at minimum and makes sure that the image has boot critical and bus enumerator drivers. Also, WES7 aggregates numerous feature packages to form one single large package, thereby reducing the number of feature packages by almost 1/6 (~150 packages) that of WES2009.
By eliminating some of the old legacy drivers, the number of driver packages in WES7 is reduced by nearly half as compared to WES2009. There are approximately 100 important drivers that are included in the eCore package6, giving OEM developers a jump start in building their image. In WES2009, all drivers had to be manually selected in the Target Designer as components, making the image building process quite tedious.
There are no more familiar SLX project files in WES7. With WES2009, an SLX file was used to keep track of project settings like which components were are added along with their configuration settings. Starting with WES7, all project configurations, like features, drivers, applications, language packs, etc. to add, are maintained in an XML-based file called the Answer File. When you use ICE to add various components to your OS image, all of the actions are entered as corresponding XML entries into the Answer File, including the DS (32-bit or 64-bit) you have selected. The output of ICE is always an Answer File.
In WES2009, a developer would check the dependencies of the components before building the final image. This dependency check concept is also included in WES7, but in the form of "validating" the XML-based Answer File. You can go to Validate → Validate Only at anytime in ICE to check if all of the dependencies are satisfied or not. Please see Appendix-I: Target Designer and ICE Screenshots for an overview of the layout.
Although WES7 has comparable tools to WES2009, it provides a completely different methodology for creating images. By eliminating the time consuming process of selecting all of the appropriate components, drivers, etc. to produce a functional image, OEMs are able to focus on building the project's application.
WES7 comes with 3 installation discs:
The Toolkit DVD is used to install the IDE tool ICE and associated DS (32-bit/64-bit) on the development computer. The 32-bit and 64-bit Windows Embedded Standard 7 DVDs are bootable WinPE DVDs that contain the Image Builder Wizard (IBW) and the corresponding 32-bit or 64-bit DS. These DVDs are typically used to boot into Windows PE on the target device and apply the runtime image created with ICE or to prototype image creation using the wizard and various templates available in IBW.
|Image Building Model||WES2009||WES7|
|ICE/Advanced Method||IBW/Express Method|
|1. System Analysis||Tap.exe → Devices.pmq → Import into TD||Tap.exe → Devices.pmq → Import into ICE||
|2. Image Configuration||Configured on developer machine using TD||Configured on developer machine using ICE|
|3. Image Customization||Using Component Designer||Using ICE|
|4. Project File||SLX file is ready||Valid Answer File is ready|
|5. Image Building7||Build on developer machine using TD||Always build on target device using IBW|
|6. Adding Components Post-Build||Requires rebuilding of the entire image||Can be added offline and online using DISM|
With WES7, the image building process has been completely overhauled. In WES2009, a developer first has to configure and build an image on the development system. With WES7, a developer can bypass the ICE/Advanced Method entirely and quickly install (configure and build) WES7 images directly on the target device using the IBW/Express Method for quick prototyping by booting off of WinPE/IBW DVDs as shown above.
The Image Builder (IBW) program can install images in two modes:
The following steps occur in Interactive Mode upon booting from the IBW WinPE disc:
In Unattended Mode an Answer File (Unattended.xml) can be created using ICE on the development machine and supplied to the Image Builder when booting from the IBW WinPE disc on the target device, thereby automating the installation process. To create fully unattended Answer Files please refer to .
No matter whether ICE is used to create an Answer File or IBW is used directly on the target device, Image Builder ultimately does all of the heavy lifting on the target device to build the WES7 image. In certain situations, this can be a major drawback.
With WES2009, when you copy your image generated from Target Designer to your target device media (like a hard drive or CompactFlash) and boot from it, the FBA (First Boot Agent) program is executed to install the rest of the WES209 system. The FBA process has phases numbered from 0 to 65535 . Depending on the phases, different settings are applied to the image. One can configure actions that take place at a particular FBA phase by creating a component using Component Designer.
With WES7, the FBA model is replaced by a Configuration Pass  model which is executed by IBW on the target device. Following is a table describing the passes that are executed8 on the target device during installation of a WES7 image:
|Image Builder Logical Phases||Configuration Pass||Executed by||Command to Execute the Pass|
|Windows Welcome||oobeSystem||Yes||Yes||sysprep /oobe|
One can configure various actions to occur in each of these passes by modifying the properties in the Answer File for that particular pass using ICE.
The image building process has gone through a significant change since WES2009. With WES7, OEM developers are able to configure and build images over the target device and have the option of completely automating WES7 installation. Although replacing the entire FBA process with the IBW and configuration passes introduces a significant learning curve, this new model gives OEM developers more control and flexibility over the image configuration and building process. One drawback of the building model is that if the target device is low performance, it could take hours to build the WES7 image9.
In WES2009, one of the common methods to test (and sometimes deploy) an image on the target device during the development phase is to copy the contents from the "C:\Windows Embedded Images" folder on the development machine to the root (usually Drive C:) of a Windows XP bootable partition on a target storage device (hard drive, CompactFlash, USB drive, etc.) and boot from it.
With WES7, if you are using 10ICE, once you finish preparing your Answer File you have the following options to test/deploy your image:
Note: Unlike WES2009, this bootable CD/DVD is not for running WES7 directly from the CD/DVD-ROM.
Once you prepare your install media (UFD or CD/DVD), you can boot from it on the target device and IBW will start installing WES7.
Following is a brief table comparing alternate deployment methods:
|PXE Boot||Yes||No (replaced by WDS12)|
Let's take a look at an example which describes the differences between WES2009 and WES7 when sysprep'ing an image, which is a common technique used for mass deployment on target devices.
|1. Image configuration||Target Designer on development machine||ICE on development machine|
|2. Add Sysprep tool||Add "Sysprep Component14"||N/A|
|3. Configure Sysprep tool||Right-clicking on the component||N/A|
|4. Booting image on target device||Your preferred method to boot||Your preferred method to boot|
|5. Locate sysprep tool directory on target image||C:\sysprep\sysprep||C:\Windows\System32\sysprep|
|6. Sysprep your target image||
sysprep15.exe -reseal -reboot
-- or --
fbreseal.exe (if you are using the "System Cloning" component )
sysprep.exe /generalize /oobe16/reboot
-- or --
sysprep.exe /generalize /audit /reboot
As you can see, the switch reseal is replaced by the generalize. They both achieve the same purpose (removing SID, computer name, user settings, etc.). Many features of the Sysprep tool, such as the audit and factory mode, were not supported in WES2009 for the ConfigMgr OSD17 functionality which is now supported in WES7. You also need to delete the Sysprep tool in WES7, unlike in WES2009 where it is deleted automatically once you have resealed your image. In WES7, a developer can reseal an image multiple times until it is finalized, whereas in WES2009 you can only reseal an image once.
A lot of the new deployment methods in WES7 make uses of the existing Windows 7 deployment techniques. This allows OEMs to leverage the benefits of these advanced technologies while simultaneously reducing the learning curve.
Log files are another area where things have changed considerably with respect to WES7. In WES2009, to debug issues during the image install (FBA) process, one would typically look at the following files in the installation partition (usually C:\) of the target device:
With WES7, the Image Builder logs its actions in different directories and storage media (ram disk, hard drive, etc.) depending upon the installation phase18:
|Installation Phase||Log Files Location||User Interaction|
(Just when WinPE is about to load)
|No log files are created||Before clicking "Build an Image" or "Deploy an Answer File or WIM"|
|Before clicking "Next" on the disk configuration screen|
|Once disk partition is selected|
|After installation completes and windows prepares to start for the first time|
|C:\Windows.~BT\Sources\Rollback\*||If fatal error occurs and setup fails and decides to roll back|
C:\Windows\System32\Sysprep\Panther - Generalize
C:\Windows\Panther\Unattendgc - Unattended actions
|When you execute Sysprep command with different parameters|
A RAM disk is destroyed if system power is turned off. To copy the log files from the RAM disk before the power is turned off:
Use the net use command to move the log files from the X:\ drive to a network share.
With WES7, there are two separate log files, as a part of SetupAPI logs, for driver and applications installation:
Sysprep logs Image Builder actions in different directories depending upon the configuration pass. Because the generalize pass deletes certain Image Builder log files, Sysprep logs generalize actions outside of the standard Image Builder log files.
The location and names of log files have changed completely in WES7 because of the fundamental change in the Image Building process (IBW instead of FBA). Moreover, log files in WES7 are categorized into different locations and file names depending upon the type of action performed by Image Builder and DISM. This makes the debugging process much easier and intuitive.
The latest WIM (Windows Imaging Format), a "hardware-agnostic" file-based format, can be used for maintaining HAL-independent images. You can start by creating a WES7 core image, capturing it with the ImageX  tool that is supplied with WES7, and then mounting the image (.wim) on your development computer file system and making any necessary updates (servicing) offline (adding drivers, applying 3rd party updates, installating applications, etc.) for your respective platform. Because several images can be created inside one single image, maintaining WES7 images is very easy and efficient. However, separate images are required for different processor architectures (32-bit vs. 64-bit platforms) since the drivers are not compatible across processor architectures.
WES2009 has a deployment tool called SDI (System Development Image) which is somewhat similar to ImageX, although it lacks some of the advanced features like servicing images offline and creating multiple instances of images in one single file .
With new technologies like WIM and tools like ImageX, WES7 provides a cost-effective means of maintaining OS images since a single image can be deployed on a variety of target platforms.
The localization i.e. language packs (LPs) support in WES7 has been redesigned from scratch and now includes language-neutral design in terms of OS components, meaning that the localized resources are now separated from the non-localized resources. This enables OEMs to quickly localize a particular language, fixing non-localized bugs without having to re-ship the entire binary.
|What can be localized?|
|Language Install Source||MUI||Language Packs (LPs)|
|Adding Language(s) Offline||No||Yes|
|Included in Main Install Disc||No||Yes (in DS)|
|No. of Languages Support||23||36|
|OS Binaries||Have to be fully localized||Only apply relevant LP|
|Resulting OS Footprint||Large||Small|
Moreover, the LPs only contain language resources for the corresponding design-neutral parts of the feature sets, drivers, etc. and hence the resulting OS footprint is smaller in size relative to WES2009.
The improvement in WES7 localization reduces the need for servicing security and feature updates significantly.
Applications for WES7 can be developed with tools like Visual Studio 2008 just like in WES2009 or XPe. Almost all target applications in embedded projects have dependencies which need to be satisfied by the OS image in order for the application to run successfully in Windows. These dependencies are classified into two categories:
In WES2009, one would use 3rd party tools like Process Monitor21 and Dependency Walker Path  to find dependencies. The relevant components could then be included in the SLX file. This can be a time consuming and frustrating process, especially when an application has a significant number of dependencies.
In WES7, there are new tools that make including applications in a WES7 project nearly seamless. First of all, ICE has an SDA (Static Dependency Analyzer) tool for analyzing static dependences for .exe, .dll, and .msi files. This is done in ICE via Tools → Analyze Static Dependences and then browsing to the file (usually an .exe, .dll, etc.) to analyze.
SDA is not a comprehensive dependency analysis tool and the Process Monitor must be used in WES7 to analyze required dynamic dependencies22. However, there is another tool called Package Mapper  for WES7 which can process output from Process Monitor, which is usually a file that lists all of the binaries that are required and maps those dependencies (binaries) to WES7 packages. The resulting file is an Answer File which can now be consumed by ICE. The process looks like this:
Templates are where WES7 steals the show from WES2009 when it comes to supporting a target application. The output of Process Monitor contains unnecessary files, noise, registry entries, etc. and thus it could take weeks to identify dependencies. WES7 now has a dedicated website which provides various templates for your target application. For example, let's say you want "Windows Live Messenger" in your target OS image. Instead of analyzing dependencies that are required to run the Messenger service, you can simply go the WES7 compatible application website  and download the "Windows Live Messenger" template and import it into ICE via File → Import → Import Template. The imported template can then be added to the Answer File.
Finding target application dependencies can be a challenging and time-consuming process. From an OEM perspective, the powerful tools in WES7 help save time and resources by performing all of the complicated analysis beforehand and providing a ready-to-use template for a project. Independent Software Vendors (ISVs) can work with Microsoft's WES team to create and upload a template for their application on the WES7 Compatible Application website .
With its new set of powerful tools and technologies, WES7 is a dramatic improvement over its predecessors, especially given the degree of customization and flexibility that it offers in regards to image configuration and building. WES7 delivers the power and reliability of the Windows 7 operating systems, while also providing the essential features of an embedded operating system - componentization and customization. The focus has been to reduce time to market by enabling OEM developers to spend more time on their core competency of application development and less time figuring out the correct set of components required to build a fully-functional image. Although WES7 lacks a few features which were available with its predecessors, overall it is a sleek embedded operating system. There is definitely a significant learning curve in transitioning to WES7, but the benefits far outweigh the costs.
WES7 Migration: Adobe Acrobat (PDF) version of this white paper
WES7 Migration: Presentation version of this white paper
OS Compatibility: Windows Embedded compatibility information for VersaLogic SBCs
Software Downloads: Windows Embedded Board Support Packages (BSPs) for VersaLogic SBCs
Windows Embedded: OS resources and KnowledgeBase articles
|.txt, .jpg, .etc files||
.sys, .dll files
So far, various differences between the tools and the process of configuring images at a higher conceptual level have been discussed. In this section we will provide actual examples of how things are done differently in WES7 as compared to WES2009. In particular we will focus on how to add 3rd party material in an OS image.
They can be run in Pass 1, 4, 6, 7
Driver files (INF-based) can be added in Pass 1, 2, 5
This folder is always inserted in Pass 1